Arrêt du PC pendant scan

Bonjour,
Bonjour,
Depuis quelques temps, lorsque je lance spy-bot, ad-aware et maintenant l'nalyse anti virus Norton, mon PC s'arrête tout silpmement. Cela le fait aussi lorsque je lance a-square.
Lorsque je lance hijackthis, j'obtiens ceci:
Logfile of HijackThis v1.99.1
Scan saved at 09:30:09, on 09/03/2008
Platform: Windows XP SP2 (WinNT 5.01.2600)
MSIE: Internet Explorer v7.00 (7.00.6000.16608)

Running processes:
G:\WINDOWS\System32\smss.exe
G:\WINDOWS\system32\winlogon.exe
G:\WINDOWS\system32\services.exe
G:\WINDOWS\system32\lsass.exe
G:\WINDOWS\system32\svchost.exe
G:\WINDOWS\System32\svchost.exe
G:\WINDOWS\system32\svchost.exe
G:\Program Files\Fichiers communs\Symantec Shared\ccSvcHst.exe
G:\WINDOWS\system32\spoolsv.exe
G:\Program Files\a-squared Free\a2service.exe
G:\Program Files\Norton Ghost\Agent\VProSvc.exe
G:\WINDOWS\system32\nvsvc32.exe
G:\Program Files\Symantec\LiveUpdate\ALUSchedulerSvc.exe
G:\WINDOWS\system32\svchost.exe
G:\Program Files\Anonymizer\Anonymizer Software\Common\AnonMgmtSvc.exe
G:\Program Files\Raxco\PerfectDisk\PDSched.exe
G:\Program Files\Fichiers communs\Symantec Shared\VAScanner\comHost.exe
G:\Program Files\Fichiers communs\Symantec Shared\CCPD-LC\symlcsvc.exe
G:\WINDOWS\Explorer.EXE
G:\WINDOWS\System32\spool\DRIVERS\W32X86\3\E_FATI9CE.EXE
G:\WINDOWS\RTHDCPL.EXE
G:\WINDOWS\system32\RUNDLL32.EXE
G:\Program Files\Fichiers communs\Symantec Shared\ccApp.exe
G:\PROGRA~1\GOTOSO~1\VADERE~1\Vaderetro_Oe.exe
G:\WINDOWS\system32\MMTray.exe
G:\WINDOWS\system32\MMTray2k.exe
G:\WINDOWS\system32\MMTrayLSI.exe
G:\Program Files\Winamp\winampa.exe
G:\Program Files\Norton Ghost\Agent\VProTray.exe
G:\Program Files\Anonymizer\Anonymizer Software\Anonymizer.exe
G:\WINDOWS\system32\ctfmon.exe
G:\Program Files\Messenger\msmsgs.exe
G:\Program Files\Logitech\Desktop Messenger\8876480\Program\LogitechDesktopMessenger.exe
G:\Program Files\Logitech\SetPoint\SetPoint.exe
G:\Program Files\Webshots\webshots.scr
G:\Program Files\Fichiers communs\Logitech\KhalShared\KHALMNPR.EXE
G:\Program Files\Anonymizer\Anonymizer Software\common\AnonProxy.exe
G:\Program Files\Internet Explorer\iexplore.exe
C:\Program Files\HijackThis\HijackThis.exe

O2 - BHO: (no name) - {1E8A6170-7264-4D0F-BEAE-D42A53123C75} - G:\Program Files\Fichiers communs\Symantec Shared\coShared\Browser\1.5\NppBho.dll
O2 - BHO: e-Carte Bleue Browser Helper Object - {2E03C0FD-4C48-43A7-9A54-00240C70FF16} - G:\WINDOWS\system32\BhoECart.dll
O2 - BHO: Spybot-S&D IE Protection - {53707962-6F74-2D53-2644-206D7942484F} - G:\Program Files\Spybot - Search & Destroy\SDHelper.dll
O2 - BHO: EpsonToolBandKicker Class - {E99421FB-68DD-40F0-B4AC-B7027CAE2F1A} - G:\Program Files\EPSON\EPSON Web-To-Page\EPSON Web-To-Page.dll
O3 - Toolbar: Afficher Norton Toolbar - {90222687-F593-4738-B738-FBEE9C7B26DF} - G:\Program Files\Fichiers communs\Symantec Shared\coShared\Browser\1.5\UIBHO.dll
O3 - Toolbar: EPSON Web-To-Page - {EE5D279F-081B-4404-994D-C6B60AAEBA6D} - G:\Program Files\EPSON\EPSON Web-To-Page\EPSON Web-To-Page.dll
O4 - HKLM\..\Run: [EPSON Stylus Photo RX420 Series] G:\WINDOWS\System32\spool\DRIVERS\W32X86\3\E_FATI9CE.EXE /P31 "EPSON Stylus Photo RX420 Series" /O6 "USB001" /M "Stylus Photo RX420"
O4 - HKLM\..\Run: [RTHDCPL] RTHDCPL.EXE
O4 - HKLM\..\Run: [Alcmtr] ALCMTR.EXE
O4 - HKLM\..\Run: [nwiz] nwiz.exe /install
O4 - HKLM\..\Run: [NvMediaCenter] RUNDLL32.EXE G:\WINDOWS\system32\NvMcTray.dll,NvTaskbarInit
O4 - HKLM\..\Run: [ccApp] "G:\Program Files\Fichiers communs\Symantec Shared\ccApp.exe"
O4 - HKLM\..\Run: [VadeRetro Outlook Express & Windows Mail] "G:\PROGRA~1\GOTOSO~1\VADERE~1\Vaderetro_Oe.exe"
O4 - HKLM\..\Run: [MMTray] MMTray.exe
O4 - HKLM\..\Run: [MMTray2K] MMTray2k.exe
O4 - HKLM\..\Run: [MMTrayLSI] MMTrayLSI.exe
O4 - HKLM\..\Run: [WinampAgent] G:\Program Files\Winamp\winampa.exe
O4 - HKLM\..\Run: [JMB36X IDE Setup] G:\WINDOWS\RaidTool\xInsIDE.exe
O4 - HKLM\..\Run: [Norton Ghost 12.0] "G:\Program Files\Norton Ghost\Agent\VProTray.exe"
O4 - HKLM\..\Run: [Kernel and Hardware Abstraction Layer] KHALMNPR.EXE
O4 - HKLM\..\Run: [Symantec PIF AlertEng] "G:\Program Files\Fichiers communs\Symantec Shared\PIF\{B8E1DD85-8582-4c61-B58F-2F227FCA9A08}\PIFSvc.exe" /a /m "G:\Program Files\Fichiers communs\Symantec Shared\PIF\{B8E1DD85-8582-4c61-B58F-2F227FCA9A08}\AlertEng.dll"
O4 - HKCU\..\Run: [Anonymizer] G:\Program Files\Anonymizer\Anonymizer Software\Anonymizer.exe -nogui
O4 - HKCU\..\Run: [ctfmon.exe] G:\WINDOWS\system32\ctfmon.exe
O4 - HKCU\..\Run: [MSMSGS] "G:\Program Files\Messenger\msmsgs.exe" /background
O4 - Startup: Webshots.lnk = G:\Program Files\Webshots\Launcher.exe
O4 - Global Startup: Logitech Desktop Messenger.lnk = G:\Program Files\Logitech\Desktop Messenger\8876480\Program\LogitechDesktopMessenger.exe
O4 - Global Startup: Logitech SetPoint.lnk = G:\Program Files\Logitech\SetPoint\SetPoint.exe
O9 - Extra button: (no name) - {DFB852A3-47F8-48C4-A200-58CAB36FD2A2} - G:\Program Files\Spybot - Search & Destroy\SDHelper.dll
O9 - Extra 'Tools' menuitem: Spybot - Search && Destroy Configuration - {DFB852A3-47F8-48C4-A200-58CAB36FD2A2} - G:\Program Files\Spybot - Search & Destroy\SDHelper.dll
O16 - DPF: {6A344D34-5231-452A-8A57-D064AC9B7862} (Symantec Download Manager) - https://webdl.symantec.com/activex/symdlmgr.cab
O21 - SSODL: WPDShServiceObj - {AAA288BA-9A4C-45B0-95D7-94D524869DB5} - G:\WINDOWS\system32\WPDShServiceObj.dll
O23 - Service: a-squared Free Service (a2free) - Emsi Software GmbH - G:\Program Files\a-squared Free\a2service.exe
O23 - Service: Anonymizer Management Service (AnonMgmtSvc) - Unknown owner - G:\Program Files\Anonymizer\Anonymizer Software\Common\AnonMgmtSvc.exe" (file missing)
O23 - Service: Symantec Event Manager (ccEvtMgr) - Unknown owner - G:\Program Files\Fichiers communs\Symantec Shared\ccSvcHst.exe" /h ccCommon (file missing)
O23 - Service: Symantec Settings Manager (ccSetMgr) - Unknown owner - G:\Program Files\Fichiers communs\Symantec Shared\ccSvcHst.exe" /h ccCommon (file missing)
O23 - Service: Symantec Lic NetConnect service (CLTNetCnService) - Unknown owner - G:\Program Files\Fichiers communs\Symantec Shared\ccSvcHst.exe" /h ccCommon (file missing)
O23 - Service: COM Host (comHost) - Symantec Corporation - G:\Program Files\Fichiers communs\Symantec Shared\VAScanner\comHost.exe
O23 - Service: Google Updater Service (gusvc) - Google - G:\Program Files\Google\Common\Google Updater\GoogleUpdaterService.exe
O23 - Service: InstallDriver Table Manager (IDriverT) - Macrovision Corporation - G:\Program Files\Fichiers communs\InstallShield\Driver\1150\Intel 32\IDriverT.exe
O23 - Service: LiveUpdate - Symantec Corporation - G:\PROGRA~1\Symantec\LIVEUP~1\LUCOMS~1.EXE
O23 - Service: LiveUpdate Notice Service Ex (LiveUpdate Notice Ex) - Unknown owner - G:\Program Files\Fichiers communs\Symantec Shared\ccSvcHst.exe" /h ccCommon (file missing)
O23 - Service: LiveUpdate Notice Service - Unknown owner - G:\Program Files\Fichiers communs\Symantec Shared\PIF\{B8E1DD85-8582-4c61-B58F-2F227FCA9A08}\PIFSvc.exe" /m "G:\Program Files\Fichiers communs\Symantec Shared\PIF\{B8E1DD85-8582-4c61-B58F-2F227FCA9A08}\PifEng.dll (file missing)
O23 - Service: Norton Ghost - Symantec Corporation - G:\Program Files\Norton Ghost\Agent\VProSvc.exe
O23 - Service: NVIDIA Display Driver Service (NVSvc) - NVIDIA Corporation - G:\WINDOWS\system32\nvsvc32.exe
O23 - Service: PDEngine - Raxco Software, Inc. - G:\Program Files\Raxco\PerfectDisk\PDEngine.exe
O23 - Service: PDScheduler (PDSched) - Raxco Software, Inc. - G:\Program Files\Raxco\PerfectDisk\PDSched.exe
O23 - Service: Planificateur LiveUpdate automatique - Symantec Corporation - G:\Program Files\Symantec\LiveUpdate\ALUSchedulerSvc.exe
O23 - Service: Symantec Core LC - Symantec Corporation - G:\Program Files\Fichiers communs\Symantec Shared\CCPD-LC\symlcsvc.exe

Quellqu'un peut-il m'aider et me dire ce que je dois virer ou faire ?
Merci d'avance
Régine