windows vista très lent

bonjour,
on m'a indiqué de venir dans cette section, de poster un rapport hijackthis et d'enlever avast. pour avast par quel antivirus (gratuit) je peux le remplacer.

Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 13:48:38, on 13/03/2008
Platform: Windows Vista (WinNT 6.00.1904)
MSIE: Internet Explorer v7.00 (7.00.6000.16609)
Boot mode: Normal

Running processes:
C:\Windows\system32\taskeng.exe
C:\Windows\system32\Dwm.exe
C:\Windows\Explorer.EXE
C:\Program Files\Windows Defender\MSASCui.exe
C:\Windows\RtHDVCpl.exe
C:\Acer\Empowering Technology\eDataSecurity\eDSLoader.exe
C:\Acer\Empowering Technology\eAudio\eAudio.exe
C:\Windows\System32\mobsync.exe
C:\Windows\System32\rundll32.exe
C:\Program Files\Acer Arcade Deluxe\Play Movie\PMVService.exe
C:\Program Files\Apoint2K\Apoint.exe
C:\Windows\BR040286.exe
C:\Program Files\Alwil Software\Avast4\ashDisp.exe
C:\Program Files\Grisoft\AVG Anti-Spyware 7.5\avgas.exe
C:\Program Files\Java\jre1.6.0_03\bin\jusched.exe
C:\Program Files\Windows Sidebar\sidebar.exe
C:\Program Files\Windows Media Player\wmpnscfg.exe
C:\Program Files\Spybot - Search & Destroy\TeaTimer.exe
C:\Windows\system32\wbem\unsecapp.exe
C:\Windows\System32\rundll32.exe
C:\Program Files\Windows Sidebar\sidebar.exe
C:\Users\MARIE-~1\AppData\Local\Temp\RtkBtMnt.exe
C:\Acer\Empowering Technology\EPOWER\EPOWER_DMC.EXE
C:\Acer\Empowering Technology\ACER.EMPOWERING.FRAMEWORK.SUPERVISOR.EXE
C:\Acer\Empowering Technology\eRecovery\ERAGENT.EXE
C:\Program Files\Apoint2K\Apntex.exe
C:\Program Files\Internet Explorer\ieuser.exe
C:\Program Files\Internet Explorer\iexplore.exe
C:\Program Files\MSN Messenger\msnmsgr.exe
C:\Program Files\MSN Messenger\livecall.exe
C:\Program Files\Windows Media Player\wmplayer.exe
C:\Windows\system32\Macromed\Flash\FlashUtil9b.exe
C:\Users\Marie-Eve\Downloads\HiJackThis.exe

R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://orange.fr/
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = http://fr.fr.acer.yahoo.com
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://fr.fr.acer.yahoo.com
R1 - HKCU\Software\Microsoft\Internet Explorer\SearchURL,(Default) = http://fr.rd.yahoo.com/customize/ycomp/defaults/su/*http://fr.yahoo.com
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName =
R3 - URLSearchHook: Yahoo! Toolbar avec bloqueur de fenêtres pop-up - {EF99BD32-C1FB-11D2-892F-0090271D4F88} - (no file)
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
O2 - BHO: Spybot-S&D IE Protection - {53707962-6F74-2D53-2644-206D7942484F} - C:\PROGRA~1\SPYBOT~1\SDHelper.dll
O2 - BHO: SSVHelper Class - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Program Files\Java\jre1.6.0_03\bin\ssv.dll
O2 - BHO: (no name) - {7E853D72-626A-48EC-A868-BA8D5E23E045} - (no file)
O3 - Toolbar: Acer eDataSecurity Management - {5CBE3B7C-1E47-477e-A7DD-396DB0476E29} - C:\Windows\system32\eDStoolbar.dll
O4 - HKLM\..\Run: [Windows Defender] %ProgramFiles%\Windows Defender\MSASCui.exe -hide
O4 - HKLM\..\Run: [ALaunch] C:\Acer\ALaunch\AlaunchClient.exe
O4 - HKLM\..\Run: [RtHDVCpl] RtHDVCpl.exe
O4 - HKLM\..\Run: [eDataSecurity Loader] C:\Acer\Empowering Technology\eDataSecurity\eDSloader.exe
O4 - HKLM\..\Run: [eAudio] "C:\Acer\Empowering Technology\eAudio\eAudio.exe"
O4 - HKLM\..\Run: [Adobe Reader Speed Launcher] "C:\Program Files\Adobe\Reader 8.0\Reader\Reader_sl.exe"
O4 - HKLM\..\Run: [NvSvc] RUNDLL32.EXE C:\Windows\system32\nvsvc.dll,nvsvcStart
O4 - HKLM\..\Run: [NvCplDaemon] RUNDLL32.EXE C:\Windows\system32\NvCpl.dll,NvStartup
O4 - HKLM\..\Run: [NvMediaCenter] RUNDLL32.EXE C:\Windows\system32\NvMcTray.dll,NvTaskbarInit
O4 - HKLM\..\Run: [LManager] C:\PROGRA~1\LAUNCH~1\LManager.exe
O4 - HKLM\..\Run: [PlayMovie] "C:\Program Files\Acer Arcade Deluxe\Play Movie\PMVService.exe"
O4 - HKLM\..\Run: [Apoint] C:\Program Files\Apoint2K\Apoint.exe
O4 - HKLM\..\Run: [Acer Tour Reminder] C:\Acer\AcerTour\Reminder.exe
O4 - HKLM\..\Run: [WarReg_PopUp] C:\Acer\WR_PopUp\WarReg_PopUp.exe
O4 - HKLM\..\Run: [SetPanel] C:\Acer\APanel\APanel.cmd
O4 - HKLM\..\Run: [NeroFilterCheck] C:\Program Files\Common Files\Ahead\Lib\NeroCheck.exe
O4 - HKLM\..\Run: [BisonInst0402] C:\Windows\BR040286.exe
O4 - HKLM\..\Run: [avast!] C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
O4 - HKLM\..\Run: [!AVG Anti-Spyware] "C:\Program Files\Grisoft\AVG Anti-Spyware 7.5\avgas.exe" /minimized
O4 - HKLM\..\Run: [SunJavaUpdateSched] "C:\Program Files\Java\jre1.6.0_03\bin\jusched.exe"
O4 - HKCU\..\Run: [Sidebar] C:\Program Files\Windows Sidebar\sidebar.exe /autoRun
O4 - HKCU\..\Run: [Acer Tour Reminder] C:\Acer\AcerTour\Reminder.exe
O4 - HKCU\..\Run: [WMPNSCFG] C:\Program Files\Windows Media Player\WMPNSCFG.exe
O4 - HKCU\..\Run: [SpybotSD TeaTimer] C:\Program Files\Spybot - Search & Destroy\TeaTimer.exe
O4 - Global Startup: Empowering Technology Launcher.lnk = ?
O4 - Global Startup: Microsoft Office.lnk = C:\Program Files\Microsoft Office\Office10\OSA.EXE
O8 - Extra context menu item: E&xporter vers Microsoft Excel - res://C:\PROGRA~1\MICROS~2\Office10\EXCEL.EXE/3000
O8 - Extra context menu item: Envoyer à &Bluetooth - C:\Program Files\WIDCOMM\Logiciel Bluetooth\btsendto_ie_ctx.htm
O9 - Extra button: (no name) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.6.0_03\bin\ssv.dll
O9 - Extra 'Tools' menuitem: Console Java (Sun) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.6.0_03\bin\ssv.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
O12 - Plugin for .spop: C:\Program Files\Internet Explorer\Plugins\NPDocBox.dll
O13 - Gopher Prefix:
O23 - Service: ALaunch Service (ALaunchService) - Unknown owner - C:\Acer\ALaunch\ALaunchSvc.exe
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: AVG Anti-Spyware Guard - GRISOFT s.r.o. - C:\Program Files\Grisoft\AVG Anti-Spyware 7.5\guard.exe
O23 - Service: Symantec Lic NetConnect service (CLTNetCnService) - Unknown owner - C:\Program Files\Common Files\Symantec Shared\ccSvcHst.exe (file missing)
O23 - Service: eDSService.exe (eDataSecurity Service) - HiTRSUT - C:\Acer\Empowering Technology\eDataSecurity\eDSService.exe
O23 - Service: eLock Service (eLockService) - Acer Inc. - C:\Acer\Empowering Technology\eLock\Service\eLockServ.exe
O23 - Service: eNet Service - Acer Inc. - C:\Acer\Empowering Technology\eNet\eNet Service.exe
O23 - Service: eRecovery Service (eRecoveryService) - Acer Inc. - C:\Acer\Empowering Technology\eRecovery\eRecoveryService.exe
O23 - Service: eSettings Service (eSettingsService) - Unknown owner - C:\Acer\Empowering Technology\eSettings\Service\capuserv.exe
O23 - Service: Google Updater Service (gusvc) - Google - C:\Program Files\Google\Common\Google Updater\GoogleUpdaterService.exe
O23 - Service: hpdj - Unknown owner - C:\Users\MARIE-~1\AppData\Local\Temp\hpdj.exe (file missing)
O23 - Service: LightScribeService Direct Disc Labeling Service (LightScribeService) - Hewlett-Packard Company - C:\Program Files\Common Files\LightScribe\LSSrvc.exe
O23 - Service: MobilityService - Unknown owner - C:\Acer\Mobility Center\MobilityService.exe
O23 - Service: NBService - Nero AG - C:\Program Files\Nero\Nero 7\Nero BackItUp\NBService.exe
O23 - Service: Cyberlink RichVideo Service(CRVS) (RichVideo) - Unknown owner - C:\Program Files\CyberLink\Shared Files\RichVideo.exe
O23 - Service: SBSD Security Center Service (SBSDWSCService) - Safer Networking Ltd. - C:\Program Files\Spybot - Search & Destroy\SDWinSec.exe
O23 - Service: ePower Service (WMIService) - acer - C:\Acer\Empowering Technology\ePower\ePowerSvc.exe
O23 - Service: XAudioService - Conexant Systems, Inc. - C:\Windows\system32\DRIVERS\xaudio.exe

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End of file - 8587 bytes

merci de votre aide