Grazie a chi risponde.
Ho un porblema....Spesso cade la connessione (il problema nn è del gestore dell'adls poichè ho un altro computer collegato ad internet).Avast riconosce un sacco di virus uno dopo l'altro e sempre nella stessa cartella C:\Windows\system32\anjsild.exe (questo è solo un esempio poichè ogno volta cambia il nome del file)
Qualcuno mi aiuta?sa cosa posso fare?

vi lascio il log file se puo' servire

Logfile of HijackThis v1.99.1
Scan saved at 10.21.16, on 29/08/2006
Platform: Windows XP (WinNT 5.01.2600)
MSIE: Internet Explorer v6.00 (6.00.2600.0000)

Running processes:
C:\WINDOWS\System32\smss.exe
C:\WINDOWS\system32\winlogon.exe
C:\WINDOWS\system32\services.exe
C:\WINDOWS\system32\lsass.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\System32\svchost.exe
C:\WINDOWS\system32\spoolsv.exe
C:\WINDOWS\Explorer.EXE
C:\Programmi\ScanSoft\OmniPageSE\opware32.exe
C:\Programmi\HP\HP Software Update\HPWuSchd2.exe
C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
C:\WINDOWS\System32\logon.exe
C:\WINDOWS\System32\Isass.exe
C:\WINDOWS\System32\iexplore.exe
C:\WINDOWS\System32\ctfmon.exe
C:\Programmi\Alwil Software\Avast4\aswUpdSv.exe
C:\Programmi\HP\Digital Imaging\bin\hpqgalry.exe
C:\Programmi\Alwil Software\Avast4\ashServ.exe
C:\Programmi\File comuni\Microsoft Shared\VS7DEBUG\MDM.EXE
C:\Programmi\Canon\MultiPASS4\MPSERVIC.EXE
C:\WINDOWS\System32\nvsvc32.exe
C:\WINDOWS\System32\svchost.exe
C:\WINDOWS\update\updmgr.exe
C:\Programmi\Alwil Software\Avast4\ashMaiSv.exe
C:\Programmi\Alwil Software\Avast4\ashWebSv.exe
C:\WINDOWS\System32\wuauclt.exe
C:\Programmi\Internet Explorer\iexplore.exe
C:\Programmi\Canon\MultiPASS4\MPDBMgr.exe
C:\Programmi\WinRAR\WinRAR.exe
C:\DOCUME~1\Admin\IMPOST~1\Temp\Rar$EX00.547\HijackThis.exe

R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://www.google.it/
R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Local Page =
R0 - HKLM\Software\Microsoft\Internet Explorer\Main,Local Page =
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Collegamenti
R3 - Default URLSearchHook is missing
O2 - BHO: AcroIEHlprObj Class - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Programmi\Adobe\Acrobat 5.0\Reader\ActiveX\AcroIEHelper.ocx
O2 - BHO: Google Toolbar Helper - {AA58ED58-01DD-4d91-8333-CF10577473F7} - c:\programmi\google\googletoolbar1.dll
O2 - BHO: Class - {DDB54E0A-C0A3-8B16-0B57-FCDC1CF443F6} - (no file)
O3 - Toolbar: &Radio - {8E718888-423F-11D2-876E-00A0C9082467} - C:\WINDOWS\System32\msdxm.ocx
O3 - Toolbar: &Google - {2318C2B1-4965-11d4-9B18-009027A5CD4F} - c:\programmi\google\googletoolbar1.dll
O4 - HKLM\..\Run: [Cmaudio] RunDll32 cmicnfg.cpl,CMICtrlWnd
O4 - HKLM\..\Run: [NeroCheck] C:\WINDOWS\System32\NeroCheck.exe
O4 - HKLM\..\Run: [Omnipage] C:\Programmi\ScanSoft\OmniPageSE\opware32.exe
O4 - HKLM\..\Run: [NvCplDaemon] RUNDLL32.EXE C:\WINDOWS\System32\NvCpl.dll,NvStartup
O4 - HKLM\..\Run: [nwiz] nwiz.exe /install
O4 - HKLM\..\Run: [HP Software Update] "C:\Programmi\HP\HP Software Update\HPWuSchd2.exe"
O4 - HKLM\..\Run: [avast!] C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
O4 - HKLM\..\Run: [Windows Logon Application] C:\WINDOWS\System32\logon.exe
O4 - HKLM\..\Run: [Microsoft (R) Windows Update Manager] C:\WINDOWS\update\updmgr.exe
O4 - HKLM\..\Run: [Local Security Authority Service] C:\WINDOWS\System32\Isass.exe
O4 - HKLM\..\Run: [Microsoft Internet Explorer] C:\WINDOWS\System32\iexplore.exe
O4 - HKLM\..\Run: [Windows Explorer] C:\WINDOWS\System32\explorer.exe
O4 - HKCU\..\Run: [CTFMON.EXE] C:\WINDOWS\System32\ctfmon.exe
O4 - Global Startup: Avvio rapido di HP Image Zone.lnk = C:\Programmi\HP\Digital Imaging\bin\hpqthb08.exe
O4 - Global Startup: HP Digital Imaging Monitor.lnk = C:\Programmi\HP\Digital Imaging\bin\hpqtra08.exe
O8 - Extra context menu item: E&sporta in Microsoft Excel - res://C:\PROGRA~1\MICROS~2\OFFICE11\EXCEL.EXE/3000
O9 - Extra button: Ricerche - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\PROGRA~1\MICROS~2\OFFICE11\REFIEBAR.DLL
O12 - Plugin for .spop: C:\Programmi\Internet Explorer\Plugins\NPDocBox.dll
O16 - DPF: {8E0D4DE5-3180-4024-A327-4DFAD1796A8D} (MessengerStatsClient Class) - http://messenger.zone.msn.com/binary/MessengerStatsClient.cab31267.cab
O16 - DPF: {F6BF0D00-0B2A-4A75-BF7B-F385591623AF} (Solitaire Showdown Class) - http://messenger.zone.msn.com/binary/SolitaireShowdown.cab31267.cab
O17 - HKLM\System\CCS\Services\Tcpip\..\{7BE70699-6641-410F-BC78-2A560A309FD1}: NameServer = 85.37.17.11 151.99.125.1
O18 - Protocol: livecall - {828030A1-22C1-4009-854F-8E305202313F} - C:\PROGRA~1\MSNMES~1\MSGRAP~1.DLL
O18 - Protocol: msnim - {828030A1-22C1-4009-854F-8E305202313F} - C:\PROGRA~1\MSNMES~1\MSGRAP~1.DLL
O23 - Service: avast! iAVS4 Control Service (aswUpdSv) - Unknown owner - C:\Programmi\Alwil Software\Avast4\aswUpdSv.exe
O23 - Service: avast! Antivirus - Unknown owner - C:\Programmi\Alwil Software\Avast4\ashServ.exe
O23 - Service: avast! Mail Scanner - Unknown owner - C:\Programmi\Alwil Software\Avast4\ashMaiSv.exe" /service (file missing)
O23 - Service: avast! Web Scanner - Unknown owner - C:\Programmi\Alwil Software\Avast4\ashWebSv.exe" /service (file missing)
O23 - Service: MpService - Canon Inc. - C:\Programmi\Canon\MultiPASS4\MPSERVIC.EXE
O23 - Service: NVIDIA Display Driver Service (NVSvc) - NVIDIA Corporation - C:\WINDOWS\System32\nvsvc32.exe
O23 - Service: Windows Update Manager (UpdateManager) - Unknown owner - C:\WINDOWS\update\updmgr.exe

Credo che faresti bene a considerare l'ipotesi di dover formattare l'hard disk.
In ogni caso è consigliabile che ti salvi su un cd tutti i file che hai paura di perdere.