Help trojan

Salut et merci de te pencher sur mon blem, voici le rapport: Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 09:49:34, on 11/10/2008
Platform: Windows XP SP3 (WinNT 5.01.2600)
MSIE: Internet Explorer v7.00 (7.00.6000.20861)
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\svchost.exe
C:\WINDOWS\System32\svchost.exe
C:\WINDOWS\Explorer.EXE
C:\WINDOWS\system32\spoolsv.exe
C:\Program Files\Avira\AntiVir PersonalEdition Classic\sched.exe
C:\Program Files\Avira\AntiVir PersonalEdition Classic\avguard.exe
C:\WINDOWS\system32\nvsvc32.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\system32\RUNDLL32.EXE
C:\Program Files\Avira\AntiVir PersonalEdition Classic\avgnt.exe
C:\Program Files\Lexmark 6200 Series\lxbumon.exe
C:\Program Files\Lexmark 6200 Series\ezprint.exe
C:\Program Files\Google\Gmail Notifier\gnotify.exe
C:\Program Files\TaskSwitchXP\TaskSwitchXP.exe
C:\WINDOWS\system32\ctfmon.exe
C:\Program Files\Ensemble clavier et souris sans fil Labtec\MagicKey.exe
C:\Program Files\Ensemble clavier et souris sans fil Labtec\MulMouse.exe
C:\Program Files\Ensemble clavier et souris sans fil Labtec\OSD.EXE
C:\WINDOWS\system32\lxbucoms.exe
C:\WINDOWS\explorer.exe
C:\Program Files\TechSmith\SnagIt 8\SnagIt32.exe
C:\Program Files\TechSmith\SnagIt 8\TSCHelp.exe
C:\Program Files\TechSmith\SnagIt 8\SnagPriv.exe
C:\Program Files\Trend Micro\HijackThis\HijackThis.exe
C:\WINDOWS\system32\wuauclt.exe

R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Page = https://www.google.fr/?gws_rd=ssl
R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = https://www.google.fr/?gws_rd=ssl
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 - HKLM\Software\Microsoft\Internet Explorer\Main,Start Page = https://www.msn.com/fr-fr/?ocid=iehp
R0 - HKLM\Software\Microsoft\Internet Explorer\Search,SearchAssistant =
R0 - HKLM\Software\Microsoft\Internet Explorer\Search,CustomizeSearch =
R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Window Title = Windows Ultimate Edition
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Liens
O1 - Hosts: ;Tag&rename
O2 - BHO: SnagIt Toolbar Loader - {00C6482D-C502-44C8-8409-FCE54AD9C208} - C:\Program Files\TechSmith\SnagIt 8\SnagItBHO.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
O3 - Toolbar: SnagIt - {8FF5E183-ABDE-46EB-B09E-D2AAB95CABE3} - C:\Program Files\TechSmith\SnagIt 8\SnagItIEAddin.dll
O4 - HKLM\..\Run: [NvCplDaemon] RUNDLL32.EXE C:\WINDOWS\system32\NvCpl.dll,NvStartup
O4 - HKLM\..\Run: [nwiz] nwiz.exe /install
O4 - HKLM\..\Run: [NvMediaCenter] RUNDLL32.EXE C:\WINDOWS\system32\NvMcTray.dll,NvTaskbarInit
O4 - HKLM\..\Run: [avgnt] "C:\Program Files\Avira\AntiVir PersonalEdition Classic\avgnt.exe" /min
O4 - HKLM\..\Run: [lxbumon.exe] "C:\Program Files\Lexmark 6200 Series\lxbumon.exe"
O4 - HKLM\..\Run: [FaxCenterServer] "C:\Program Files\Lexmark Fax Solutions\fm3032.exe" /s
O4 - HKLM\..\Run: [EzPrint] "C:\Program Files\Lexmark 6200 Series\ezprint.exe"
O4 - HKLM\..\Run: [{0228e555-4f9c-4e35-a3ec-b109a192b4c2}] C:\Program Files\Google\Gmail Notifier\gnotify.exe
O4 - HKLM\..\RunOnce: [WIAWizardMenu] RUNDLL32.EXE C:\WINDOWS\system32\sti_ci.dll,WiaCreateWizardMenu
O4 - HKCU\..\Run: [TaskSwitchXP] C:\Program Files\TaskSwitchXP\TaskSwitchXP.exe
O4 - HKCU\..\Run: [ctfmon.exe] C:\WINDOWS\system32\ctfmon.exe
O4 - HKUS\S-1-5-19\..\Run: [TaskSwitchXP] C:\Program Files\TaskSwitchXP\TaskSwitchXP.exe (User 'SERVICE LOCAL')
O4 - HKUS\S-1-5-19\..\RunOnce: [nltide_2] regsvr32 /s /n /i:U shell32 (User 'SERVICE LOCAL')
O4 - HKUS\S-1-5-20\..\Run: [TaskSwitchXP] C:\Program Files\TaskSwitchXP\TaskSwitchXP.exe (User 'SERVICE RÉSEAU')
O4 - HKUS\S-1-5-20\..\RunOnce: [nltide_2] regsvr32 /s /n /i:U shell32 (User 'SERVICE RÉSEAU')
O4 - HKUS\S-1-5-18\..\Run: [TaskSwitchXP] C:\Program Files\TaskSwitchXP\TaskSwitchXP.exe (User 'SYSTEM')
O4 - HKUS\S-1-5-18\..\RunOnce: [nltide_2] regsvr32 /s /n /i:U shell32 (User 'SYSTEM')
O4 - HKUS\.DEFAULT\..\Run: [TaskSwitchXP] C:\Program Files\TaskSwitchXP\TaskSwitchXP.exe (User 'Default user')
O4 - HKUS\.DEFAULT\..\RunOnce: [nltide_2] regsvr32 /s /n /i:U shell32 (User 'Default user')
O4 - Global Startup: Activer l'ensemble clavier et souris sans fil Labtec.lnk = C:\Program Files\Ensemble clavier et souris sans fil Labtec\MagicKey.exe
O8 - Extra context menu item: E&xporter vers Microsoft Excel - res://C:\PROGRA~1\MICROS~1\Office12\EXCEL.EXE/3000
O9 - Extra button: Research - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\PROGRA~1\MICROS~1\Office12\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
O23 - Service: Avira AntiVir Personal - Free Antivirus Scheduler (AntiVirScheduler) - Avira GmbH - C:\Program Files\Avira\AntiVir PersonalEdition Classic\sched.exe
O23 - Service: Avira AntiVir Personal - Free Antivirus Guard (AntiVirService) - Avira GmbH - C:\Program Files\Avira\AntiVir PersonalEdition Classic\avguard.exe
O23 - Service: lxbu_device - Lexmark International, Inc. - C:\WINDOWS\system32\lxbucoms.exe
O23 - Service: NVIDIA Display Driver Service (NVSvc) - NVIDIA Corporation - C:\WINDOWS\system32\nvsvc32.exe
O23 - Service: Microsoft Office Diagnostics Service (odserv) - Unknown owner - C:\Program Files\Fichiers communs\Microsoft Shared\OFFICE12\ODSERV.EXE