Probable virus sur ordinateur tout neuf, HELP!!

J'ai acheté mon ordinateur il y a maintenant 3mois et j'ai l'impression qu'il commence a avoir des virus, il est encore neuf et j'aimerais qu'il reste en bon état, est-ce que quelqu'un pourrait m'aider pour que je fasse les tests necessaires afin de verifier cela? Merci d'avance

Mon ordi est plus lent, il a eu quelques petits problemes, et j'ai parfois des messages d'erreur qui s'affichent...

Je m'en rappelle plus désolée, en plus j'ai eu recemment un trojan et je ne suis pas sûre qu'il ait été supprimé

Rapport HiJack This:

Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 11:36:04, on 05/12/2007
Platform: Windows Vista (WinNT 6.00.1904)
MSIE: Internet Explorer v7.00 (7.00.6000.16546)
Boot mode: Normal

Running processes:
C:\Windows\system32\Dwm.exe
C:\Windows\Explorer.EXE
C:\Windows\system32\taskeng.exe
C:\Program Files\Windows Defender\MSASCui.exe
C:\hp\support\hpsysdrv.exe
C:\Program Files\Hewlett-Packard\On-Screen OSD Indicator\OSD.exe
C:\Program Files\Intel\Intel Matrix Storage Manager\IAAnotif.exe
C:\Windows\RtHDVCpl.exe
C:\Program Files\HP\HP Software Update\hpwuSchd2.exe
C:\Program Files\Common Files\Symantec Shared\PIF\{B8E1DD85-8582-4c61-B58F-2F227FCA9A08}\PIFSvc.exe
C:\Program Files\Alwil Software\Avast4\ashDisp.exe
C:\Windows\System32\hkcmd.exe
C:\Windows\System32\igfxpers.exe
C:\Program Files\Windows Sidebar\sidebar.exe
C:\Program Files\Windows Media Player\wmpnscfg.exe
C:\Windows\system32\igfxsrvc.exe
C:\Windows\System32\mobsync.exe
C:\hp\kbd\kbd.exe
C:\Program Files\Windows Media Player\wmplayer.exe
C:\Users\Deborah\Documents\eMule\emule.exe
C:\Windows\system32\taskeng.exe
C:\Program Files\VideoLAN\VLC\vlc.exe
C:\Program Files\Internet Explorer\ieuser.exe
C:\Program Files\Internet Explorer\iexplore.exe
C:\Windows\system32\Macromed\Flash\FlashUtil9d.exe
C:\Program Files\Internet Explorer\iexplore.exe
C:\Windows\system32\SearchFilterHost.exe
C:\Program Files\Trend Micro\HijackThis\HijackThis.exe

R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Page = http://go.microsoft.com/fwlink/?LinkId=54896
R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://www.google.fr/
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = http://ie.redirect.hp.com/svs/rdr? [...] pf=desktop
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://ie.redirect.hp.com/svs/rdr? [...] pf=desktop
R0 - HKLM\Software\Microsoft\Internet Explorer\Search,SearchAssistant =
R0 - HKLM\Software\Microsoft\Internet Explorer\Search,CustomizeSearch =
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName =
O1 - Hosts: ::1 localhost
O2 - BHO: Aide pour le lien d'Adobe PDF Reader - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Program Files\Common Files\Adobe\Acrobat\ActiveX\AcroIEHelper.dll (file missing)
O2 - BHO: (no name) - {7E853D72-626A-48EC-A868-BA8D5E23E045} - (no file)
O2 - BHO: Google Toolbar Helper - {AA58ED58-01DD-4d91-8333-CF10577473F7} - c:\program files\google\googletoolbar2.dll
O3 - Toolbar: &Google - {2318C2B1-4965-11d4-9B18-009027A5CD4F} - c:\program files\google\googletoolbar2.dll
O4 - HKLM\..\Run: [Windows Defender] %ProgramFiles%\Windows Defender\MSASCui.exe -hide
O4 - HKLM\..\Run: [hpsysdrv] c:\hp\support\hpsysdrv.exe
O4 - HKLM\..\Run: [KBD] C:\HP\KBD\KbdStub.EXE
O4 - HKLM\..\Run: [OsdMaestro] "C:\Program Files\Hewlett-Packard\On-Screen OSD Indicator\OSD.exe"
O4 - HKLM\..\Run: [IAAnotif] "C:\Program Files\Intel\Intel Matrix Storage Manager\Iaanotif.exe"
O4 - HKLM\..\Run: [RtHDVCpl] RtHDVCpl.exe
O4 - HKLM\..\Run: [HP Software Update] c:\Program Files\HP\HP Software Update\HPWuSchd2.exe
O4 - HKLM\..\Run: [Symantec PIF AlertEng] "C:\Program Files\Common Files\Symantec Shared\PIF\{B8E1DD85-8582-4c61-B58F-2F227FCA9A08}\PIFSvc.exe" /a /m "C:\Program Files\Common Files\Symantec Shared\PIF\{B8E1DD85-8582-4c61-B58F-2F227FCA9A08}\AlertEng.dll"
O4 - HKLM\..\Run: [avast!] C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
O4 - HKLM\..\Run: [NBKeyScan] "C:\Program Files\Nero\Nero8\Nero BackItUp\NBKeyScan.exe"
O4 - HKLM\..\Run: [IgfxTray] C:\Windows\system32\igfxtray.exe
O4 - HKLM\..\Run: [HotKeysCmds] C:\Windows\system32\hkcmd.exe
O4 - HKLM\..\Run: [Persistence] C:\Windows\system32\igfxpers.exe
O4 - HKLM\..\Run: [Adobe Reader Speed Launcher] "C:\Program Files\Adobe\Reader 8.0\Reader\Reader_sl.exe"
O4 - HKLM\..\RunOnce: [Launcher] %WINDIR%\SMINST\launcher.exe
O4 - HKCU\..\Run: [Sidebar] C:\Program Files\Windows Sidebar\sidebar.exe /autoRun
O4 - HKCU\..\Run: [WMPNSCFG] C:\Program Files\Windows Media Player\WMPNSCFG.exe
O4 - HKCU\..\Run: [BgMonitor_{79662E04-7C6C-4d9f-84C7-88D8A56B10AA}] "C:\Program Files\Common Files\Nero\Lib\NMBgMonitor.exe"
O4 - HKUS\S-1-5-19\..\Run: [Sidebar] %ProgramFiles%\Windows Sidebar\Sidebar.exe /detectMem (User 'SERVICE LOCAL')
O4 - HKUS\S-1-5-19\..\Run: [WindowsWelcomeCenter] rundll32.exe oobefldr.dll,ShowWelcomeCenter (User 'SERVICE LOCAL')
O4 - HKUS\S-1-5-20\..\Run: [Sidebar] %ProgramFiles%\Windows Sidebar\Sidebar.exe /detectMem (User 'SERVICE RÉSEAU')
O8 - Extra context menu item: E&xporter vers Microsoft Excel - res://C:\PROGRA~1\MICROS~3\Office12\EXCEL.EXE/3000
O9 - Extra button: Envoyer à OneNote - {2670000A-7350-4f3c-8081-5663EE0C6C49} - C:\PROGRA~1\MICROS~3\Office12\ONBttnIE.dll
O9 - Extra 'Tools' menuitem: &Envoyer à OneNote - {2670000A-7350-4f3c-8081-5663EE0C6C49} - C:\PROGRA~1\MICROS~3\Office12\ONBttnIE.dll
O9 - Extra button: Research - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\PROGRA~1\MICROS~3\Office12\REFIEBAR.DLL
O13 - Gopher Prefix:
O16 - DPF: {5D6F45B3-9043-443D-A792-115447494D24} (UnoCtrl Class) - http://messenger.zone.msn.com/FR-F [...] E_UNO1.cab
O16 - DPF: {C3F79A2B-B9B4-4A66-B012-3EE46475B072} (MessengerStatsClient Class) - http://messenger.zone.msn.com/bina [...] b56907.cab
O23 - Service: avast! iAVS4 Control Service (aswUpdSv) - ALWIL Software - C:\Program Files\Alwil Software\Avast4\aswUpdSv.exe
O23 - Service: avast! Antivirus - ALWIL Software - C:\Program Files\Alwil Software\Avast4\ashServ.exe
O23 - Service: avast! Mail Scanner - ALWIL Software - C:\Program Files\Alwil Software\Avast4\ashMaiSv.exe
O23 - Service: avast! Web Scanner - ALWIL Software - C:\Program Files\Alwil Software\Avast4\ashWebSv.exe
O23 - Service: Google Updater Service (gusvc) - Google - C:\Program Files\Google\Common\Google Updater\GoogleUpdaterService.exe
O23 - Service: Intel(R) Matrix Storage Event Monitor (IAANTMON) - Intel Corporation - C:\Program Files\Intel\Intel Matrix Storage Manager\Iaantmon.exe
O23 - Service: InstallDriver Table Manager (IDriverT) - Macrovision Corporation - c:\Program Files\Common Files\InstallShield\Driver\1050\Intel 32\IDriverT.exe
O23 - Service: LightScribeService Direct Disc Labeling Service (LightScribeService) - Hewlett-Packard Company - c:\Program Files\Common Files\LightScribe\LSSrvc.exe
O23 - Service: LiveUpdate - Symantec Corporation - C:\PROGRA~1\Symantec\LIVEUP~1\LUCOMS~1.EXE
O23 - Service: LiveUpdate Notice Service Ex (LiveUpdate Notice Ex) - Unknown owner - c:\Program Files\Common Files\Symantec Shared\ccSvcHst.exe (file missing)
O23 - Service: LiveUpdate Notice Service - Symantec Corporation - C:\Program Files\Common Files\Symantec Shared\PIF\{B8E1DD85-8582-4c61-B58F-2F227FCA9A08}\PIFSvc.exe
O23 - Service: Planificateur LiveUpdate automatique - Symantec Corporation - C:\Program Files\Symantec\LiveUpdate\ALUSchedulerSvc.exe
O23 - Service: RoxMediaDB9 - Sonic Solutions - c:\Program Files\Common Files\Roxio Shared\9.0\SharedCOM\RoxMediaDB9.exe
O23 - Service: stllssvr - MicroVision Development, Inc. - c:\Program Files\Common Files\SureThing Shared\stllssvr.exe

--
End of file - 7544 bytes

Ok merci alr et désolée pour le derangement