Arret aléatoire de mon ordinateur

Bonjour,
Depuis quelques jours mon ordinateur s'arrête brusquement et de façon aléatoire. Est-ce qu'il peut y a voir une raison toute simple de paramétrage ou bien je suis infecté par un virus. J'utilise le pare feu windows, l'antivirus gratuit AVIRA, Spybot régulièrement et ccleaner.
J'ai essayé un scan en ligne mais je n'ai pas pu aller au bout à cause d'un arret du PC. cela se produit souvent lorsque je suis sur internet et que je veux changer de site ou suivre un lien

je joins mon log HijackThis que je ne sais pas analyser

merci de votre aide
Cordialement

Logfile of HijackThis v1.99.1
Scan saved at 23:22:53, on 19/01/2009
Platform: Windows XP SP3 (WinNT 5.01.2600)
MSIE: Internet Explorer v7.00 (7.00.6000.16762)

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:\Program Files\Avira\AntiVir PersonalEdition Classic\avguard.exe
C:\WINDOWS\Explorer.EXE
C:\Program Files\Fichiers communs\Acronis\Schedule2\schedul2.exe
C:\Program Files\Adobe\Photoshop Elements 4.0\PhotoshopElementsFileAgent.exe
C:\WINDOWS\RTHDCPL.EXE
C:\Program Files\Medion Info Display\MdionLCM.exe
C:\WINDOWS\CNYHKey.exe
C:\Program Files\Avira\AntiVir PersonalEdition Classic\sched.exe
C:\WINDOWS\system32\spool\drivers\w32x86\3\hpztsb09.exe
C:\WINDOWS\system32\CmUCReye.exe
C:\Program Files\Home Cinema\PowerCinema\Kernel\TV\CLCapSvc.exe
C:\WINDOWS\ALCFDRTM.EXE
C:\Program Files\Acronis\TrueImageHome\TrueImageMonitor.exe
C:\Program Files\Google\Common\Google Updater\GoogleUpdaterService.exe
C:\Program Files\Acronis\TrueImageHome\TimounterMonitor.exe
C:\Program Files\Fichiers communs\Acronis\Schedule2\schedhlp.exe
C:\WINDOWS\Twain_32\FlatBed\HotKey.exe
C:\PROGRA~1\TEXTBR~1.0\Bin\INSTAN~1.EXE
C:\WINDOWS\System32\svchost.exe
C:\Program Files\Avira\AntiVir PersonalEdition Classic\avgnt.exe
C:\Program Files\Java\jre6\bin\jusched.exe
C:\Program Files\Java\jre6\bin\jqs.exe
C:\WINDOWS\system32\ctfmon.exe
C:\Program Files\Fichiers communs\LightScribe\LSSrvc.exe
C:\WINDOWS\system32\nvsvc32.exe
C:\Program Files\Spybot - Search & Destroy\TeaTimer.exe
C:\Program Files\CyberLink\Shared Files\RichVideo.exe
C:\Program Files\Windows Media Player\WMPNSCFG.exe
C:\WINDOWS\system32\svchost.exe
C:\Program Files\TextBridge Pro 9.0\Bin\Ereg\Remind32.exe
C:\Program Files\Fichiers communs\Microsoft Shared\Works Shared\WkCalRem.exe
C:\Program Files\Canon\CAL\CALMAIN.exe
C:\Program Files\Home Cinema\PowerCinema\Kernel\TV\CLSched.exe
C:\WINDOWS\system32\wbem\wmiapsrv.exe
C:\Program Files\Mozilla Firefox\firefox.exe
C:\Program Files\Hijackthis Version Française\hijackthis vf.exe

R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = https://www.netvibes.com/en#General
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = https://www.msn.com/fr-fr/?ocid=iehp
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Search_URL = https://www.bing.com/?toHttps=1&redig=5FC791212101479BAFBE1A679848B1AF
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Search Page = https://www.bing.com/?toHttps=1&redig=5FC791212101479BAFBE1A679848B1AF
R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Local Page =
R1 - HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings,ProxyOverride = localhost
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Liens
O2 - BHO: Aide pour le lien d'Adobe PDF Reader - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Program Files\Fichiers communs\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: Java(tm) Plug-In SSV Helper - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Program Files\Java\jre6\bin\ssv.dll
O2 - BHO: (no name) - {7E853D72-626A-48EC-A868-BA8D5E23E045} - (no file)
O2 - BHO: Programme d'aide de l'Assistant de connexion Windows Live - {9030D464-4C02-4ABF-8ECC-5164760863C6} - C:\Program Files\Fichiers communs\Microsoft Shared\Windows Live\WindowsLiveLogin.dll
O2 - BHO: Google Toolbar Notifier BHO - {AF69DE43-7D58-4638-B6FA-CE66B5AD205D} - C:\Program Files\Google\GoogleToolbarNotifier\4.1.805.4472\swg.dll
O2 - BHO: Java(tm) Plug-In 2 SSV Helper - {DBC80044-A445-435b-BC74-9C25C1C588A9} - C:\Program Files\Java\jre6\bin\jp2ssv.dll
O2 - BHO: JQSIEStartDetectorImpl - {E7E6F031-17CE-4C07-BC86-EABFE594F69C} - C:\Program Files\Java\jre6\lib\deploy\jqs\ie\jqs_plugin.dll
O4 - HKLM\..\Run: [RTHDCPL] RTHDCPL.EXE
O4 - HKLM\..\Run: [NvCplDaemon] RUNDLL32.EXE C:\WINDOWS\system32\NvCpl.dll,NvStartup
O4 - HKLM\..\Run: [MedionVFD] "C:\Program Files\Medion Info Display\MdionLCM.exe"
O4 - HKLM\..\Run: [ledpointer] CNYHKey.exe
O4 - HKLM\..\Run: [HPDJ Taskbar Utility] C:\WINDOWS\system32\spool\drivers\w32x86\3\hpztsb09.exe
O4 - HKLM\..\Run: [CmUCRRun] C:\WINDOWS\system32\CmUCReye.exe
O4 - HKLM\..\Run: [AlcFDMonitor] C:\WINDOWS\ALCFDRTM.EXE
O4 - HKLM\..\Run: [QuickTime Task] "C:\Program Files\QuickTime\qttask.exe" -atboottime
O4 - HKLM\..\Run: [TrueImageMonitor.exe] C:\Program Files\Acronis\TrueImageHome\TrueImageMonitor.exe
O4 - HKLM\..\Run: [AcronisTimounterMonitor] C:\Program Files\Acronis\TrueImageHome\TimounterMonitor.exe
O4 - HKLM\..\Run: [Acronis Scheduler2 Service] "C:\Program Files\Fichiers communs\Acronis\Schedule2\schedhlp.exe"
O4 - HKLM\..\Run: [HotKey] C:\WINDOWS\Twain_32\FlatBed\HotKey.exe
O4 - HKLM\..\Run: [InstantAccess] C:\PROGRA~1\TEXTBR~1.0\Bin\INSTAN~1.EXE /h
O4 - HKLM\..\Run: [RegisterDropHandler] C:\PROGRA~1\TEXTBR~1.0\Bin\REGIST~1.EXE
O4 - HKLM\..\Run: [avgnt] "C:\Program Files\Avira\AntiVir PersonalEdition Classic\avgnt.exe" /min
O4 - HKLM\..\Run: [SunJavaUpdateSched] "C:\Program Files\Java\jre6\bin\jusched.exe"
O4 - HKLM\..\Run: [Adobe Reader Speed Launcher] "C:\Program Files\Adobe\Reader 8.0\Reader\Reader_sl.exe"
O4 - HKLM\..\Run: [HomePlayer] C:\Program Files\HomePlayer\HomePlayer.exe
O4 - HKLM\..\RunServices: [RegisterDropHandler] C:\PROGRA~1\TEXTBR~1.0\Bin\REGIST~1.EXE
O4 - HKCU\..\Run: [ctfmon.exe] C:\WINDOWS\system32\ctfmon.exe
O4 - HKCU\..\Run: [SpybotSD TeaTimer] C:\Program Files\Spybot - Search & Destroy\TeaTimer.exe
O4 - HKCU\..\Run: [WMPNSCFG] C:\Program Files\Windows Media Player\WMPNSCFG.exe
O4 - Startup: reminder-Enregistrement du produit ScanSoft.lnk = C:\Program Files\TextBridge Pro 9.0\Bin\Ereg\Remind32.exe
O4 - Startup: wkcalrem.LNK = C:\Program Files\Fichiers communs\Microsoft Shared\Works Shared\WkCalRem.exe
O8 - Extra context menu item: &eBay Search - res://C:\Program Files\eBay\eBay Toolbar2\eBayTb.dll/RCSearch.html
O8 - Extra context menu item: &Recherche AOL Toolbar - res://C:\Program Files\AOL Toolbar\toolbar.dll/SEARCH.HTML
O9 - Extra button: (no name) - {85d1f590-48f4-11d9-9669-0800200c9a66} - %windir%\bdoscandel.exe (file missing)
O9 - Extra 'Tools' menuitem: Uninstall BitDefender Online Scanner v8 - {85d1f590-48f4-11d9-9669-0800200c9a66} - %windir%\bdoscandel.exe (file missing)
O9 - Extra button: (no name) - {B205A35E-1FC4-4CE3-818B-899DBBB3388C} - C:\Program Files\Fichiers communs\Microsoft Shared\Encarta Search Bar\ENCSBAR.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} - %windir%\Network Diagnostic\xpnetdiag.exe (file missing)
O9 - Extra 'Tools' menuitem: @xpsp3res.dll,-20001 - {e2e2dd38-d088-4134-82b7-f2ba38496583} - %windir%\Network Diagnostic\xpnetdiag.exe (file missing)
O9 - Extra button: Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\Program Files\Messenger\msmsgs.exe
O9 - Extra 'Tools' menuitem: Windows Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\Program Files\Messenger\msmsgs.exe
O11 - Options group: [INTERNATIONAL] International*
O14 - IERESET.INF: START_PAGE_URL=https://www.free.fr/freebox/index.html
O16 - DPF: {0EB0E74A-2A76-4AB3-A7FB-9BD8C29F7F75} (CKAVWebScan Object) - https://www.kaspersky.fr/?domain=webscanner.kaspersky.fr
O16 - DPF: {17492023-C23A-453E-A040-C7C580BBF700} (Windows Genuine Advantage Validation Tool) - http://download.microsoft.com/download/E/5/6/E5611B10-0D6D-4117-8430-A67417AA88CD/LegitCheckControl.cab
O16 - DPF: {5D86DDB5-BDF9-441B-9E9E-D4730F4EE499} (BDSCANONLINE Control) - http://www.bitdefender.fr/scan8/oscan8.cab
O16 - DPF: {6414512B-B978-451D-A0D8-FCFDF33E833C} (WUWebControl Class) - http://update.microsoft.com/...
O16 - DPF: {6E32070A-766D-4EE6-879C-DC1FA91D2FC3} (MUWebControl Class) - http://update.microsoft.com/...
O18 - Protocol: bwfile-8876480 - {9462A756-7B47-47BC-8C80-C34B9B80B32B} - C:\Program Files\Logitech\Desktop Messenger\8876480\Program\GAPlugProtocol-8876480.dll
O18 - Protocol: livecall - {828030A1-22C1-4009-854F-8E305202313F} - C:\PROGRA~1\WI1F86~1\MESSEN~1\MSGRAP~1.DLL
O18 - Protocol: msnim - {828030A1-22C1-4009-854F-8E305202313F} - C:\PROGRA~1\WI1F86~1\MESSEN~1\MSGRAP~1.DLL
O18 - Protocol: wlmailhtml - {03C514A3-1EFB-4856-9F99-10D7BE1653C0} - C:\Program Files\Windows Live\Mail\mailcomm.dll
O20 - Winlogon Notify: dimsntfy - %SystemRoot%\System32\dimsntfy.dll (file missing)
O20 - Winlogon Notify: LMIinit - C:\WINDOWS\SYSTEM32\LMIinit.dll
O20 - Winlogon Notify: WgaLogon - C:\WINDOWS\SYSTEM32\WgaLogon.dll
O21 - SSODL: WPDShServiceObj - {AAA288BA-9A4C-45B0-95D7-94D524869DB5} - C:\WINDOWS\system32\WPDShServiceObj.dll
O23 - Service: Acronis Scheduler2 Service (AcrSch2Svc) - Acronis - C:\Program Files\Fichiers communs\Acronis\Schedule2\schedul2.exe
O23 - Service: Adobe Active File Monitor V4 (AdobeActiveFileMonitor4.0) - Unknown owner - C:\Program Files\Adobe\Photoshop Elements 4.0\PhotoshopElementsFileAgent.exe
O23 - Service: AntiVir PersonalEdition Classic Scheduler (AntiVirScheduler) - Avira GmbH - C:\Program Files\Avira\AntiVir PersonalEdition Classic\sched.exe
O23 - Service: AntiVir PersonalEdition Classic Guard (AntiVirService) - Avira GmbH - C:\Program Files\Avira\AntiVir PersonalEdition Classic\avguard.exe
O23 - Service: Canon Camera Access Library 8 (CCALib8) - Canon Inc. - C:\Program Files\Canon\CAL\CALMAIN.exe
O23 - Service: CyberLink Background Capture Service (CBCS) (CLCapSvc) - Unknown owner - C:\Program Files\Home Cinema\PowerCinema\Kernel\TV\CLCapSvc.exe
O23 - Service: CyberLink Task Scheduler (CTS) (CLSched) - Unknown owner - C:\Program Files\Home Cinema\PowerCinema\Kernel\TV\CLSched.exe
O23 - Service: Google Updater Service (gusvc) - Google - C:\Program Files\Google\Common\Google Updater\GoogleUpdaterService.exe
O23 - Service: InstallDriver Table Manager (IDriverT) - Macrovision Corporation - C:\Program Files\Fichiers communs\InstallShield\Driver\11\Intel 32\IDriverT.exe
O23 - Service: Java Quick Starter (JavaQuickStarterService) - Unknown owner - C:\Program Files\Java\jre6\bin\jqs.exe" -service -config "C:\Program Files\Java\jre6\lib\deploy\jqs\jqs.conf (file missing)
O23 - Service: LightScribeService Direct Disc Labeling Service (LightScribeService) - Hewlett-Packard Company - C:\Program Files\Fichiers communs\LightScribe\LSSrvc.exe
O23 - Service: NVIDIA Display Driver Service (NVSvc) - NVIDIA Corporation - C:\WINDOWS\system32\nvsvc32.exe
O23 - Service: Pml Driver HPZ12 - HP - C:\WINDOWS\system32\HPZipm12.exe
O23 - Service: Cyberlink RichVideo Service(CRVS) (RichVideo) - Unknown owner - C:\Program Files\CyberLink\Shared Files\RichVideo.exe
O23 - Service: Remote Packet Capture Protocol v.0 (experimental) (rpcapd) - Unknown owner - %ProgramFiles%\WinPcap\rpcapd.exe" -d -f "%ProgramFiles%\WinPcap\rpcapd.ini (file missing)
O23 - Service: X10 Device Network Service (x10nets) - X10 - C:\PROGRA~1\COMMON~1\X10\Common\x10nets.exe