. Premetto che ho installato sul pc Kaspersky e Spybot entrambi aggiornati, con cui ho fatto più volte una scansione.I problemi che ho riscontrato sono:
1 - la cpu è lenta anche se il pc è stato formattato un mese fa
2 - nei giorni precedenti sono stato rispedito automaticamente su questo sito: h t tp: //w w w 3.s aveus42. xorg.pl (è successo solo una volta)
3 - Improvvisamente il pc si blocca anche se sto solo girando su internet (con firefox o chrome), la cosa strana è che la schermata si blocca ma il cursore risponde ai movimenti del mouse... dopo di che non mi resta che riavviare.
4 - Al riavvio prima dell'avvio di Windows, in alto a sinistra compare alcune volte una scritta che non riesco a leggere in cui però compare qualcosa come "boot.ini".
Spero di trovare in questo forum una soluzione!
Ho visto che in precedenza siete stati efficaci! 
GRAZIE in anticipo!!
p.s. ecco il Log file di hijackthis:
Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 17.04.26, on 21/04/2010
Platform: Windows XP SP3 (WinNT 5.01.2600)
MSIE: Internet Explorer v8.00 (8.00.6001.18702)
Boot mode: Normal
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\Ati2evxx.exe
C:\windows\system32\svchost.exe
C:\windows\System32\svchost.exe
C:\windows\system32\svchost.exe
C:\windows\system32\Ati2evxx.exe
C:\windows\system32\spoolsv.exe
C:\Programmi\Creative\Shared Files\CTAudSvc.exe
C:\Programmi\Kaspersky Lab\Kaspersky Internet Security 2010\avp.exe
C:\Programmi\Bonjour\mDNSResponder.exe
C:\Programmi\File comuni\Microsoft Shared\VS7DEBUG\MDM.EXE
C:\Programmi\Microsoft\Search Enhancement Pack\SeaPort\SeaPort.exe
C:\windows\system32\svchost.exe
C:\windows\Explorer.EXE
C:\Programmi\ATI Technologies\ATI.ACE\Core-Static\MOM.EXE
C:\Programmi\Kaspersky Lab\Kaspersky Internet Security 2010\avp.exe
C:\Programmi\Spybot - Search & Destroy\TeaTimer.exe
C:\Programmi\ATI Technologies\ATI.ACE\Core-Static\ccc.exe
C:\windows\system32\ctfmon.exe
C:\windows\system32\wuauclt.exe
C:\Documents and Settings\Francesco\Impostazioni locali\Dati applicazioni\Google\Chrome\Application\chrome.exe
C:\Documents and Settings\Francesco\Impostazioni locali\Dati applicazioni\Google\Chrome\Application\chrome.exe
C:\Documents and Settings\Francesco\Impostazioni locali\Dati applicazioni\Google\Chrome\Application\chrome.exe
C:\Documents and Settings\Francesco\Impostazioni locali\Dati applicazioni\Google\Chrome\Application\chrome.exe
C:\Documents and Settings\Francesco\Impostazioni locali\Dati applicazioni\Google\Chrome\Application\chrome.exe
C:\Documents and Settings\Francesco\Impostazioni locali\Dati applicazioni\Google\Chrome\Application\chrome.exe
C:\Documents and Settings\Francesco\Impostazioni locali\Dati applicazioni\Google\Chrome\Application\chrome.exe
C:\Documents and Settings\Francesco\Documenti\Downloads\HiJackThis\HijackThis.exe
C:\windows\system32\wuauclt.exe
R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Page = http://go.microsoft.com/fwlink/?LinkId=54896
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 - HKLM\Software\Microsoft\Internet Explorer\Search,SearchAssistant =
R0 - HKLM\Software\Microsoft\Internet Explorer\Search,CustomizeSearch =
R1 - HKCU\Software\Microsoft\Internet Connection Wizard,ShellNext = http://go.microsoft.com/fwlink/?LinkId=74005
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Collegamenti
O2 - BHO: Supporto di collegamento per Adobe PDF Reader - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Programmi\File comuni\Adobe\Acrobat\ActiveX\AcroIEHelper.dll
O2 - BHO: Spybot-S&D IE Protection - {53707962-6F74-2D53-2644-206D7942484F} - C:\PROGRA~1\SPYBOT~1\SDHelper.dll
O2 - BHO: IEVkbdBHO - {59273AB4-E7D3-40F9-A1A8-6FA9CCA1862C} - C:\Programmi\Kaspersky Lab\Kaspersky Internet Security 2010\ievkbd.dll
O2 - BHO: (no name) - {5C255C8A-E604-49b4-9D64-90988571CECB} - (no file)
O2 - BHO: Search Helper - {6EBF7485-159F-4bff-A14F-B9E3AAC4465B} - C:\Programmi\Microsoft\Search Enhancement Pack\Search Helper\SEPsearchhelperie.dll
O2 - BHO: Guida per l'accesso a Windows Live - {9030D464-4C02-4ABF-8ECC-5164760863C6} - C:\Programmi\File comuni\Microsoft Shared\Windows Live\WindowsLiveLogin.dll
O2 - BHO: Windows Live Toolbar Helper - {E15A8DC0-8516-42A1-81EA-DC94EC1ACF10} - C:\Programmi\Windows Live\Toolbar\wltcore.dll
O2 - BHO: link filter bho - {E33CF602-D945-461A-83F0-819F76A199F8} - C:\Programmi\Kaspersky Lab\Kaspersky Internet Security 2010\klwtbbho.dll
O3 - Toolbar: &Windows Live Toolbar - {21FA44EF-376D-4D53-9B0F-8A89D3229068} - C:\Programmi\Windows Live\Toolbar\wltcore.dll
O4 - HKLM\..\Run: [Adobe Reader Speed Launcher] "C:\Programmi\Adobe\Reader 8.0\Reader\Reader_sl.exe"
O4 - HKLM\..\Run: [NeroFilterCheck] C:\WINDOWS\system32\NeroCheck.exe
O4 - HKLM\..\Run: [StartCCC] "C:\Programmi\ATI Technologies\ATI.ACE\Core-Static\CLIStart.exe"
O4 - HKLM\..\Run: [QuickTime Task] "C:\Programmi\QuickTime\QTTask.exe" -atboottime
O4 - HKLM\..\Run: [SamsungPCSuiteTrayApplication] C:\Programmi\Samsung\Samsung PC Studio 7\LaunchApplication.exe -startup
O4 - HKLM\..\Run: [AVP] "C:\Programmi\Kaspersky Lab\Kaspersky Internet Security 2010\avp.exe"
O4 - HKLM\..\RunOnce: [NCInstallQueue] rundll32 netman.dll,ProcessQueue
O4 - HKCU\..\Run: [AlcoholAutomount] "C:\Programmi\Alcohol Soft\Alcohol 52\AxAutoMntSrv.exe" -automount
O4 - HKCU\..\Run: [Google Update] "C:\Documents and Settings\Francesco\Impostazioni locali\Dati applicazioni\Google\Update\GoogleUpdate.exe" /c
O4 - HKCU\..\Run: [SpybotSD TeaTimer] C:\Programmi\Spybot - Search & Destroy\TeaTimer.exe
O4 - HKCU\..\Run: [ctfmon.exe] C:\windows\system32\ctfmon.exe
O4 - HKUS\S-1-5-19\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'SERVIZIO LOCALE')
O4 - HKUS\S-1-5-19\..\RunOnce: [nltide_2] regsvr32 /s /n /i:U shell32 (User 'SERVIZIO LOCALE')
O4 - HKUS\S-1-5-20\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'SERVIZIO DI RETE')
O4 - HKUS\S-1-5-20\..\RunOnce: [nltide_2] regsvr32 /s /n /i:U shell32 (User 'SERVIZIO DI RETE')
O4 - HKUS\S-1-5-18\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'SYSTEM')
O4 - HKUS\S-1-5-18\..\RunOnce: [nltide_2] regsvr32 /s /n /i:U shell32 (User 'SYSTEM')
O4 - HKUS\.DEFAULT\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'Default user')
O4 - HKUS\.DEFAULT\..\RunOnce: [nltide_2] regsvr32 /s /n /i:U shell32 (User 'Default user')
O8 - Extra context menu item: Aggiungi ad Anti-Banner - C:\Programmi\Kaspersky Lab\Kaspersky Internet Security 2010\ie_banner_deny.htm
O8 - Extra context menu item: E&sporta in Microsoft Excel - res://C:\PROGRA~1\MICROS~2\OFFICE11\EXCEL.EXE/3000
O9 - Extra button: Inserisci blog - {219C3416-8CB2-491a-A3C7-D9FCDDC9D600} - C:\Programmi\Windows Live\Writer\WriterBrowserExtension.dll
O9 - Extra 'Tools' menuitem: Inserisci &blog in Windows Live Writer - {219C3416-8CB2-491a-A3C7-D9FCDDC9D600} - C:\Programmi\Windows Live\Writer\WriterBrowserExtension.dll
O9 - Extra button: &Tastiera Virtuale - {4248FE82-7FCB-46AC-B270-339F08212110} - C:\Programmi\Kaspersky Lab\Kaspersky Internet Security 2010\klwtbbho.dll
O9 - Extra button: Ricerche - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\PROGRA~1\MICROS~2\OFFICE11\REFIEBAR.DLL
O9 - Extra button: C&ontrollo URL - {CCF151D8-D089-449F-A5A4-D9909053F20F} - C:\Programmi\Kaspersky Lab\Kaspersky Internet Security 2010\klwtbbho.dll
O9 - Extra button: (no name) - {DFB852A3-47F8-48C4-A200-58CAB36FD2A2} - C:\PROGRA~1\SPYBOT~1\SDHelper.dll
O9 - Extra 'Tools' menuitem: Spybot - Search & Destroy Configuration - {DFB852A3-47F8-48C4-A200-58CAB36FD2A2} - C:\PROGRA~1\SPYBOT~1\SDHelper.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: {6414512B-B978-451D-A0D8-FCFDF33E833C} (WUWebControl Class) - http://update.microsoft.com/windowsupda ... 9348282890
O16 - DPF: {6E32070A-766D-4EE6-879C-DC1FA91D2FC3} (MUWebControl Class) - http://www.update.microsoft.com/microso ... 1336633828
O20 - AppInit_DLLs: C:\PROGRA~1\KASPER~1\KASPER~1\mzvkbd3.dll,C:\PROGRA~1\KASPER~1\KASPER~1\kloehk.dll
O23 - Service: Ati HotKey Poller - ATI Technologies Inc. - C:\windows\system32\Ati2evxx.exe
O23 - Service: ATI Smart - Unknown owner - C:\WINDOWS\system32\ati2sgag.exe
O23 - Service: Kaspersky Internet Security (AVP) - Kaspersky Lab - C:\Programmi\Kaspersky Lab\Kaspersky Internet Security 2010\avp.exe
O23 - Service: ##Id_String1.6844F930_1628_4223_B5CC_5BB94B879762## (Bonjour Service) - Apple Computer, Inc. - C:\Programmi\Bonjour\mDNSResponder.exe
O23 - Service: Creative Audio Engine Licensing Service - Creative Labs - C:\Programmi\File comuni\Creative Labs Shared\Service\CTAELicensing.exe
O23 - Service: Creative Audio Service (CTAudSvcService) - Creative Technology Ltd - C:\Programmi\Creative\Shared Files\CTAudSvc.exe
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End of file - 8953 bytes