in pratica va molto più lento e a volte si blocca all'accensione
ho provato a fare una scansione con combofix ecco il log

ComboFix 10-10-22.05 - JAC 23/10/2010 15.28.55.1.1 - FAT32x86
Microsoft Windows XP Home Edition 5.1.2600.3.1252.39.1040.18.2047.1673 [GMT 2:00]
Eseguito da: c:\documents and settings\JAC\Desktop\ComboFix.exe
AV: Sistema Antivirus NOD32 2.70 *On-access scanning enabled* (Updated) {E5E70D32-0101-4F12-8FB0-D96ACA4F34C0}
* Creato nuovo punto di ripristino
* Resident AV is active

.

((((((((((((((((((((((((( Files Creati Da 2010-09-23 al 2010-10-23 )))))))))))))))))))))))))))))))))))
.

2010-10-23 12:58 . 2010-10-23 12:58 -------- d-----w- c:\programmi\Trend Micro
2010-10-23 12:27 . 2010-10-23 12:27 -------- d-----w- C:\FOUND.000
2010-10-19 13:23 . 2010-10-19 13:23 -------- d-----w- c:\programmi\7-Zip
2010-10-18 06:06 . 2010-10-18 06:06 -------- d-----w- c:\documents and settings\NetworkService\Impostazioni locali\Dati applicazioni\Apple
2010-10-13 18:25 . 2010-09-18 06:53 974848 ------w- c:\windows\system32\dllcache\mfc42.dll
2010-10-13 18:25 . 2010-09-18 06:53 953856 ------w- c:\windows\system32\dllcache\mfc40u.dll
2010-10-13 18:23 . 2010-08-23 16:12 617472 ------w- c:\windows\system32\dllcache\comctl32.dll
2010-10-05 04:36 . 2010-10-05 04:36 -------- d-----w- c:\programmi\Yahoo!

.
(((((((((((((((((((((((((((((((((((((((( Find3M Report )))))))))))))))))))))))))))))))))))))))))))))))))))
.
2010-09-18 10:23 . 1979-12-31 22:00 974848 ----a-w- c:\windows\system32\mfc42u.dll
2010-09-18 06:53 . 1979-12-31 22:00 974848 ----a-w- c:\windows\system32\mfc42.dll
2010-09-18 06:53 . 1979-12-31 22:00 954368 ----a-w- c:\windows\system32\mfc40.dll
2010-09-18 06:53 . 1979-12-31 22:00 953856 ----a-w- c:\windows\system32\mfc40u.dll
2010-09-09 13:33 . 1979-12-31 22:00 832512 ----a-w- c:\windows\system32\wininet.dll
2010-09-09 13:33 . 1979-12-31 22:00 78336 ----a-w- c:\windows\system32\ieencode.dll
2010-09-09 13:33 . 1979-12-31 22:00 1830912 ------w- c:\windows\system32\inetcpl.cpl
2010-09-09 13:33 . 1979-12-31 22:00 17408 ------w- c:\windows\system32\corpol.dll
2010-09-08 15:57 . 1979-12-31 22:00 389120 ----a-w- c:\windows\system32\html.iec
2010-09-01 11:51 . 1979-12-31 22:00 285824 ----a-w- c:\windows\system32\atmfd.dll
2010-09-01 07:54 . 1979-12-31 22:00 1852800 ----a-w- c:\windows\system32\win32k.sys
2010-08-27 08:02 . 1979-12-31 22:00 119808 ----a-w- c:\windows\system32\t2embed.dll
2010-08-27 05:58 . 1979-12-31 22:00 99840 ----a-w- c:\windows\system32\srvsvc.dll
2010-08-27 01:43 . 2008-05-05 05:25 5632 ----a-w- c:\windows\system32\xpsp4res.dll
2010-08-26 13:39 . 1979-12-31 22:00 357248 ----a-w- c:\windows\system32\drivers\srv.sys
2010-08-23 16:12 . 1979-12-31 22:00 617472 ----a-w- c:\windows\system32\comctl32.dll
2010-08-17 13:17 . 1979-12-31 22:00 58880 ----a-w- c:\windows\system32\spoolsv.exe
2010-08-16 08:44 . 1979-12-31 22:00 590848 ----a-w- c:\windows\system32\rpcrt4.dll
.

((((((((((((((((((((((((((((((((((((( Punti Reg Caricati ))))))))))))))))))))))))))))))))))))))))))))))))))
.
.
*Nota* i valori vuoti & legittimi/default non sono visualizzati.
REGEDIT4

[HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Run]
"Google Update"="c:\documents and settings\JAC\Impostazioni locali\Dati applicazioni\Google\Update\GoogleUpdate.exe" [2010-03-04 135664]
"msnmsgr"="c:\programmi\Windows Live\Messenger\msnmsgr.exe" [2009-07-26 3883856]
"uTorrent"="c:\programmi\uTorrent\uTorrent.exe" [2010-08-29 328568]
"OfficeSyncProcess"="c:\programmi\Microsoft Office\Office14\MSOSYNC.EXE" [2010-03-16 718208]
"WMPNSCFG"="c:\programmi\Windows Media Player\WMPNSCFG.exe" [2006-11-02 204288]
"ctfmon.exe"="c:\windows\system32\ctfmon.exe" [2008-04-14 15360]

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run]
"nod32kui"="c:\programmi\Eset\nod32kui.exe" [2010-03-03 949376]
"SoundMan"="SOUNDMAN.EXE" [2007-04-16 577536]
"LogitechCommunicationsManager"="c:\programmi\File comuni\Logitech\LComMgr\Communications_Helper.exe" [2006-10-30 284184]
"LogitechQuickCamRibbon"="c:\programmi\Logitech\QuickCam10\QuickCam10.exe" [2006-11-15 746520]
"LVCOMSX"="c:\programmi\File comuni\Logitech\LComMgr\LVComSX.exe" [2006-11-15 244512]
"AGRSMMSG"="AGRSMMSG.exe" [2004-06-29 88363]
"lxdimon.exe"="c:\programmi\Lexmark 3500-4500 Series\lxdimon.exe" [2007-05-07 435120]
"lxdiamon"="c:\programmi\Lexmark 3500-4500 Series\lxdiamon.exe" [2007-03-05 20480]
"FaxCenterServer"="c:\programmi\\Lexmark Fax Solutions\fm3032.exe" [2007-05-07 312240]
"BCSSync"="c:\programmi\Microsoft Office\Office14\BCSSync.exe" [2010-03-13 91520]
"QuickTime Task"="c:\programmi\QuickTime\QTTask.exe" [2010-03-18 421888]
"iTunesHelper"="c:\programmi\iTunes\iTunesHelper.exe" [2010-06-15 141624]
"Adobe Reader Speed Launcher"="c:\programmi\Adobe\Reader 9.0\Reader\Reader_sl.exe" [2010-09-23 35760]
"Adobe ARM"="c:\programmi\File comuni\Adobe\ARM\1.0\AdobeARM.exe" [2010-09-20 932288]

[HKEY_USERS\.DEFAULT\Software\Microsoft\Windows\CurrentVersion\Run]
"CTFMON.EXE"="c:\windows\system32\CTFMON.EXE" [2008-04-14 15360]

c:\documents and settings\JAC\Menu Avvio\Programmi\Esecuzione automatica\
Microsoft SharePoint Workspace.lnk - c:\programmi\Microsoft Office\Office14\GROOVE.EXE [2010-3-25 30969208]

[HKEY_LOCAL_MACHINE\software\microsoft\security center]
"AntiVirusOverride"=dword:00000001

[HKLM\~\services\sharedaccess\parameters\firewallpolicy\standardprofile\AuthorizedApplications\List]
"%windir%\\system32\\sessmgr.exe"=
"c:\\Programmi\\Messenger\\msmsgs.exe"=
"c:\\Programmi\\Windows Live\\Messenger\\wlcsdk.exe"=
"c:\\Programmi\\Windows Live\\Messenger\\msnmsgr.exe"=
"c:\\Programmi\\uTorrent\\uTorrent.exe"=
"%windir%\\Network Diagnostic\\xpnetdiag.exe"=
"c:\\Programmi\\Java\\jre6\\bin\\javaw.exe"=
"c:\\WINDOWS\\System32\\lxdicoms.exe"=
"c:\\Programmi\\Lexmark 3500-4500 Series\\lxdimon.exe"=
"c:\\Programmi\\Lexmark 3500-4500 Series\\App4R.exe"=
"c:\\Programmi\\Lexmark 3500-4500 Series\\lxdiamon.exe"=
"c:\\WINDOWS\\System32\\SPOOL\\drivers\\W32X86\\3\\lxdipswx.exe"=
"c:\\WINDOWS\\System32\\SPOOL\\drivers\\W32X86\\3\\lxditime.exe"=
"c:\\WINDOWS\\System32\\SPOOL\\drivers\\W32X86\\3\\lxdijswx.exe"=
"c:\\WINDOWS\\System32\\SPOOL\\DRIVERS\\W32X86\\3\\LXDIwbgw.exe"=
"c:\\Programmi\\Microsoft Office\\Office14\\GROOVE.EXE"=
"c:\\Programmi\\Microsoft Office\\Office14\\ONENOTE.EXE"=
"c:\\Programmi\\Microsoft Office\\Office14\\OUTLOOK.EXE"=
"c:\\Programmi\\Bonjour\\mDNSResponder.exe"=
"c:\\Programmi\\iTunes\\iTunes.exe"=

R1 nod32drv;nod32drv;c:\windows\system32\drivers\nod32drv.sys [03/03/2010 17.14.49 15424]
R2 lxdi_device;lxdi_device;c:\windows\system32\lxdicoms.exe -service --> c:\windows\system32\lxdicoms.exe -service [?]
R2 lxdiCATSCustConnectService;lxdiCATSCustConnectService;c:\windows\system32\spool\drivers\w32x86\3\lxdiserv.exe [24/04/2010 14.49.48 99248]
R3 ip100xp;ASUS NX1001 Network Adapter NT Driver;c:\windows\system32\drivers\ipfnd51.sys [04/03/2010 16.33.47 26752]
S2 Network WanMiniport First Position;Network WanMiniport First Position;c:\programmi\Telecom Italia\WanMiniport1st\srvany.exe [04/03/2010 15.21.39 8192]
S3 Microsoft SharePoint Workspace Audit Service;Microsoft SharePoint Workspace Audit Service;c:\programmi\Microsoft Office\Office14\GROOVE.EXE [25/03/2010 10.25.22 30969208]
S3 osppsvc;Office Software Protection Platform;c:\programmi\File comuni\Microsoft Shared\OfficeSoftwareProtectionPlatform\OSPPSVC.EXE [09/01/2010 21.37.50 4640000]
S4 sptd;sptd;c:\windows\system32\drivers\sptd.sys [07/03/2010 8.37.03 691696]
.
Contenuto della cartella 'Scheduled Tasks'

2010-10-18 c:\windows\Tasks\AppleSoftwareUpdate.job
- c:\programmi\Apple Software Update\SoftwareUpdate.exe [2009-10-22 09:50]

2010-10-19 c:\windows\Tasks\GoogleUpdateTaskUserS-1-5-21-21489301-1486246795-135365387-1005Core1cb6d3c1c307356.job
- c:\documents and settings\JAC\Impostazioni locali\Dati applicazioni\Google\Update\GoogleUpdate.exe [2010-03-04 14:37]
.
.
------- Scansione supplementare -------
.
uInternet Settings,ProxyOverride = 127.0.0.1;*.local
LSP: c:\windows\system32\imon.dll
TCP: {4B5FF208-AB71-4514-BB1D-02AF9014A4CF} = 8.8.8.8,8.8.4.4
Filter: text/xml - {807573E5-5146-11D5-A672-00B0D022E945} - c:\programmi\File comuni\Microsoft Shared\OFFICE14\MSOXMLMF.DLL
DPF: Microsoft XML Parser for Java - file://c:\windows\Java\classes\xmldso.cab
.
- - - - CHIAVI ORFANE RIMOSSE - - - -

BHO-{D4027C7F-154A-4066-A1AD-4243D8127440} - (no file)
Toolbar-{D4027C7F-154A-4066-A1AD-4243D8127440} - (no file)
HKCU-Run-LogitechSetup - d:\setup\Setup.exe



**************************************************************************

catchme 0.3.1398 W2K/XP/Vista - rootkit/stealth malware detector by Gmer, http://www.gmer.net
Rootkit scan 2010-10-23 15:34
Windows 5.1.2600 Service Pack 3 FAT NTAPI

scansione processi nascosti ...

scansione entrate autostart nascoste ...

Scansione files nascosti ...

Scansione completata con successo
Files nascosti: 0

**************************************************************************

Stealth MBR rootkit/Mebroot/Sinowal detector 0.3.7 by Gmer, http://www.gmer.net

device: opened successfully
user: MBR read successfully
called modules: ntoskrnl.exe catchme.sys CLASSPNP.SYS disk.sys ACPI.sys hal.dll >>UNKNOWN [0x89B57446]<<
kernel: MBR read successfully
detected MBR rootkit hooks:
\Driver\Disk -> CLASSPNP.SYS @ 0xf765bf28
\Driver\ACPI -> ACPI.sys @ 0xf75aecb8
\Driver\atapi -> atapi.sys @ 0xf74c6852
IoDeviceObjectType -> DeleteProcedure -> ntoskrnl.exe @ 0x805a0615
ParseProcedure -> ntoskrnl.exe @ 0x8056c3ac
\Device\Harddisk0\DR0 -> DeleteProcedure -> ntoskrnl.exe @ 0x805a0615
ParseProcedure -> ntoskrnl.exe @ 0x8056c3ac
NDIS: ASUS NX1001 Network Adapter -> SendCompleteHandler -> NDIS.sys @ 0xf743cbd4
PacketIndicateHandler -> NDIS.sys @ 0xf7448a21
SendHandler -> NDIS.sys @ 0xf743cd44
user & kernel MBR OK

**************************************************************************
.
--------------------- Dlls caricate dai processi in esecuzione ---------------------

- - - - - - - > 'winlogon.exe'(536)
c:\windows\system32\Ati2evxx.dll

- - - - - - - > 'lsass.exe'(596)
c:\windows\system32\imon.dll
c:\programmi\Eset\pr_imon.dll

- - - - - - - > 'explorer.exe'(2932)
c:\windows\system32\WININET.dll
c:\progra~1\FILECO~1\MICROS~1\OFFICE14\Cultures\office.odf
c:\progra~1\MICROS~2\Office14\1040\GrooveIntlResource.dll
c:\windows\system32\msi.dll
c:\windows\system32\WPDShServiceObj.dll
c:\windows\system32\PortableDeviceTypes.dll
c:\windows\system32\PortableDeviceApi.dll
.
Ora fine scansione: 2010-10-23 15:36:30
ComboFix-quarantined-files.txt 2010-10-23 13:36

Pre-Run: 57.019.990.016 byte disponibili
Post-Run: 56.994.168.832 byte disponibili

WindowsXP-KB310994-SP2-Home-BootDisk-ITA.exe
[boot loader]
timeout=2
default=multi(0)disk(0)rdisk(0)partition(1)\WINDOWS
[operating systems]
c:\cmdcons\BOOTSECT.DAT="Microsoft Windows Recovery Console" /cmdcons
UnsupportedDebug="do not select this" /debug
multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP Home Edition" /noexecute=optin /fastdetect

- - End Of File - - 0345AC40D86261977AB7DC7200C0AD18