Ciao ragazzi, circa una settimana fà sono andato ad accendere il pc e dal desktop era sparita l'immagine di sfondo e la barra degli strumenti è diventata grigia, ho rimesso tutto apposto ma da allora il pc è ancora più lento di quanto già non lo fosse e inoltre ci sono delle righe sullo schermo e la scritta stand by al momento dello spegnimento è oscurata( non cliccabile), vi posto qui anche il log appena fatto di hijackthis se può servirvi e inoltre da ieri ho provato a cancellare karsperski e installare avast e pc tools.
Grazie di cuore a quanti mi aiuteranno

Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 22.44.00, on 15/02/2009
Platform: Windows XP SP2 (WinNT 5.01.2600)
MSIE: Internet Explorer v7.00 (7.00.6000.16791)
Boot mode: Normal

Running processes:
C:\WINDOWS\System32\smss.exe
C:\WINDOWS\system32\csrss.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\svchost.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\system32\svchost.exe
C:\Programmi\Alwil Software\Avast4\aswUpdSv.exe
C:\Programmi\Alwil Software\Avast4\ashServ.exe
C:\WINDOWS\system32\spoolsv.exe
C:\Programmi\File comuni\Microsoft Shared\VS7DEBUG\MDM.EXE
C:\Programmi\PC Tools Firewall Plus\FWService.exe
C:\Programmi\Spyware Doctor\pctsAuxs.exe
C:\Programmi\Spyware Doctor\pctsSvc.exe
C:\WINDOWS\system32\svchost.exe
C:\Programmi\Alwil Software\Avast4\ashMaiSv.exe
C:\Programmi\Alwil Software\Avast4\ashWebSv.exe
C:\WINDOWS\System32\alg.exe
C:\Programmi\Spyware Doctor\pctsTray.exe
C:\WINDOWS\Explorer.EXE
C:\Programmi\Java\jre1.6.0_04\bin\jusched.exe
C:\WINDOWS\SOUNDMAN.EXE
C:\Programmi\ASUS\WLAN Card Utilities\Center.exe
C:\Programmi\HiYo\bin\HiYo.exe
C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
C:\Programmi\PC Tools Firewall Plus\FirewallGUI.exe
C:\WINDOWS\system32\ctfmon.exe
C:\Programmi\Picasa2\PicasaMediaDetector.exe
C:\Programmi\File comuni\Ahead\Lib\NMBgMonitor.exe
C:\Programmi\Messenger\msmsgs.exe
C:\Programmi\File comuni\Ahead\Lib\NMIndexStoreSvr.exe
C:\Programmi\Windows Live\Messenger\msnmsgr.exe
C:\Programmi\Google\GoogleToolbarNotifier\GoogleToolbarNotifier.exe
C:\Programmi\Skype\Phone\Skype.exe
C:\WINDOWS\system32\wuauclt.exe
C:\Programmi\WinZip\WZQKPICK.EXE
C:\Programmi\OpenOffice.org 2.4\program\soffice.exe
C:\Programmi\Mozilla Firefox\firefox.exe
C:\Programmi\OpenOffice.org 2.4\program\soffice.BIN
C:\Programmi\File comuni\Ahead\Lib\NMIndexingService.exe
C:\Programmi\Skype\Plugin Manager\skypePM.exe
C:\Programmi\Java\jre1.6.0_04\bin\jucheck.exe
C:\Programmi\Windows Live\Messenger\usnsvc.exe
C:\Programmi\Trend Micro\HijackThis\HijackThis.exe
C:\WINDOWS\system32\wbem\wmiprvse.exe

R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://www.libero.it/
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = http://go.microsoft.com/fwlink/?LinkId=69157
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Search_URL = http://go.microsoft.com/fwlink/?LinkId=54896
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Search Page = http://go.microsoft.com/fwlink/?LinkId=54896
R0 - HKLM\Software\Microsoft\Internet Explorer\Main,Start Page = http://go.microsoft.com/fwlink/?LinkId=69157
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Collegamenti
O2 - BHO: AcroIEHelperStub - {18DF081C-E8AD-4283-A596-FA578C2EBDC3} - C:\Programmi\File comuni\Adobe\Acrobat\ActiveX\AcroIEHelperShim.dll
O2 - BHO: Skype add-on (mastermind) - {22BF413B-C6D2-4d91-82A9-A0F997BA588C} - C:\Programmi\Skype\Toolbars\Internet Explorer\SkypeIEPlugin.dll
O2 - BHO: SSVHelper Class - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Programmi\Java\jre1.6.0_04\bin\ssv.dll
O2 - BHO: (no name) - {7E853D72-626A-48EC-A868-BA8D5E23E045} - (no file)
O2 - BHO: Windows Live Sign-in Helper - {9030D464-4C02-4ABF-8ECC-5164760863C6} - C:\Programmi\File comuni\Microsoft Shared\Windows Live\WindowsLiveLogin.dll
O2 - BHO: Google Toolbar Helper - {AA58ED58-01DD-4d91-8333-CF10577473F7} - c:\programmi\google\googletoolbar1.dll
O2 - BHO: Google Toolbar Notifier BHO - {AF69DE43-7D58-4638-B6FA-CE66B5AD205D} - C:\Programmi\Google\GoogleToolbarNotifier\3.1.807.1746\swg.dll
O3 - Toolbar: &Google - {2318C2B1-4965-11d4-9B18-009027A5CD4F} - c:\programmi\google\googletoolbar1.dll
O4 - HKLM\..\Run: [Cmaudio] RunDll32 cmicnfg.cpl,CMICtrlWnd
O4 - HKLM\..\Run: [NeroFilterCheck] C:\Programmi\File comuni\Ahead\Lib\NeroCheck.exe
O4 - HKLM\..\Run: [SunJavaUpdateSched] "C:\Programmi\Java\jre1.6.0_04\bin\jusched.exe"
O4 - HKLM\..\Run: [SoundMan] SOUNDMAN.EXE
O4 - HKLM\..\Run: [Control Center] C:\Programmi\ASUS\WLAN Card Utilities\Center.exe
O4 - HKLM\..\Run: [Hiyo] C:\Programmi\HiYo\bin\HiYo.exe /RunFromStartup
O4 - HKLM\..\Run: [Adobe Reader Speed Launcher] "C:\Programmi\Adobe\Reader 9.0\Reader\Reader_sl.exe"
O4 - HKLM\..\Run: [avast!] C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
O4 - HKLM\..\Run: [ISTray] "C:\Programmi\Spyware Doctor\pctsTray.exe"
O4 - HKLM\..\Run: [00PCTFW] "C:\Programmi\PC Tools Firewall Plus\FirewallGUI.exe" -s
O4 - HKCU\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\ctfmon.exe
O4 - HKCU\..\Run: [Picasa Media Detector] C:\Programmi\Picasa2\PicasaMediaDetector.exe
O4 - HKCU\..\Run: [BgMonitor_{79662E04-7C6C-4d9f-84C7-88D8A56B10AA}] "C:\Programmi\File comuni\Ahead\Lib\NMBgMonitor.exe"
O4 - HKCU\..\Run: [MSMSGS] "C:\Programmi\Messenger\msmsgs.exe" /background
O4 - HKCU\..\Run: [msnmsgr] "C:\Programmi\Windows Live\Messenger\msnmsgr.exe" /background
O4 - HKCU\..\Run: [swg] C:\Programmi\Google\GoogleToolbarNotifier\GoogleToolbarNotifier.exe
O4 - HKCU\..\Run: [Skype] "C:\Programmi\Skype\Phone\Skype.exe" /nosplash /minimized
O4 - HKUS\S-1-5-19\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'SERVIZIO LOCALE')
O4 - HKUS\S-1-5-20\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'SERVIZIO DI RETE')
O4 - HKUS\S-1-5-18\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'SYSTEM')
O4 - HKUS\.DEFAULT\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'Default user')
O4 - Startup: OpenOffice.org 2.4.lnk = C:\Programmi\OpenOffice.org 2.4\program\quickstart.exe
O4 - Global Startup: WinZip Quick Pick.lnk = C:\Programmi\WinZip\WZQKPICK.EXE
O8 - Extra context menu item: E&sporta in Microsoft Excel - res://C:\PROGRA~1\MICROS~2\OFFICE11\EXCEL.EXE/3000
O9 - Extra button: (no name) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Programmi\Java\jre1.6.0_04\bin\ssv.dll
O9 - Extra 'Tools' menuitem: Sun Java Console - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Programmi\Java\jre1.6.0_04\bin\ssv.dll
O9 - Extra button: Skype - {77BF5300-1474-4EC7-9980-D32B190E9B07} - C:\Programmi\Skype\Toolbars\Internet Explorer\SkypeIEPlugin.dll
O9 - Extra button: Ricerche - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\PROGRA~1\MICROS~2\OFFICE11\REFIEBAR.DLL
O9 - Extra button: (no name) - {e2e2dd38-d088-4134-82b7-f2ba38496583} - C:\WINDOWS\Network Diagnostic\xpnetdiag.exe
O9 - Extra 'Tools' menuitem: @xpsp3res.dll,-20001 - {e2e2dd38-d088-4134-82b7-f2ba38496583} - C:\WINDOWS\Network Diagnostic\xpnetdiag.exe
O9 - Extra button: Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\Programmi\Messenger\msmsgs.exe
O9 - Extra 'Tools' menuitem: Windows Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\Programmi\Messenger\msmsgs.exe
O16 - DPF: {917623D1-D8E5-11D2-BE8B-00104B06BDE3} (CamImage Class) - http://85.46.64.154/activex/AxisCamControl.cab
O16 - DPF: {C3F79A2B-B9B4-4A66-B012-3EE46475B072} (MessengerStatsClient Class) - http://messenger.zone.msn.com/binary/MessengerStatsPAClient.cab56907.cab
O16 - DPF: {D27CDB6E-AE6D-11CF-96B8-444553540000} (Shockwave Flash Object) - http://fpdownload2.macromedia.com/get/shockwave/cabs/flash/swflash.cab
O18 - Protocol: skype4com - {FFC8B962-9B40-4DFF-9458-1830C7DD7F5D} - C:\PROGRA~1\FILECO~1\Skype\SKYPE4~1.DLL
O23 - Service: avast! iAVS4 Control Service (aswUpdSv) - ALWIL Software - C:\Programmi\Alwil Software\Avast4\aswUpdSv.exe
O23 - Service: avast! Antivirus - ALWIL Software - C:\Programmi\Alwil Software\Avast4\ashServ.exe
O23 - Service: avast! Mail Scanner - ALWIL Software - C:\Programmi\Alwil Software\Avast4\ashMaiSv.exe
O23 - Service: avast! Web Scanner - ALWIL Software - C:\Programmi\Alwil Software\Avast4\ashWebSv.exe
O23 - Service: Google Updater Service (gusvc) - Google - C:\Programmi\Google\Common\Google Updater\GoogleUpdaterService.exe
O23 - Service: NBService - Nero AG - C:\Programmi\Nero\Nero 7\Nero BackItUp\NBService.exe
O23 - Service: NMIndexingService - Nero AG - C:\Programmi\File comuni\Ahead\Lib\NMIndexingService.exe
O23 - Service: Panda Process Protection Service (PavPrSrv) - Unknown owner - C:\Programmi\File comuni\Panda Software\PavShld\pavprsrv.exe (file missing)
O23 - Service: PC Tools Firewall Plus (PCToolsFirewallPlus) - PC Tools - C:\Programmi\PC Tools Firewall Plus\FWService.exe
O23 - Service: PC Tools Auxiliary Service (sdAuxService) - PC Tools - C:\Programmi\Spyware Doctor\pctsAuxs.exe
O23 - Service: PC Tools Security Service (sdCoreService) - PC Tools - C:\Programmi\Spyware Doctor\pctsSvc.exe

--
End of file - 8684 bytes

Ciao.
Il log non presenta anomalie.
Per le righe sullo schermo, potrebbe essere un problema di scheda video.
Prova a fare una scansione con SystemScan, e vediamo più dettagliatamente se c'è qualche problema .

SYSTEM SCAN

scarica sul desktop
http://www.suspectfile.com/systemscan
aprilo ed assicurati che tutte le opzioni siano spuntate, clicca su "Scan Now" al termine della scansione verranno rilasciati (sempre sul desktop all'interno della cartella suspectfile) due file.
Vai su http://www.freefilehosting.net carica il file con estensione .zip e scrivi, nella tua prossima replica l'URL per poterlo scaricare.
Carica il file su Direct Link
Ricordati d'effettuare la scansione senza connessione attiva e con l'antivirus disabilitato salvo poi riattivarlo a scansione terminata.

NB:
la durata della scansione può risultare lunga, potrebbe addirittura sembrare che il programma non stia lavorando, non preoccuparti non è così ;)

SystemScan viene riconosciuto, erroneamente, da alcuni antivirus come infetto.