pc ralenti, virus ou pas?

Bonjour à tous,
mon pc portable n'a qu'un an et déjà je le trouve assez lent,
difficile pour lui de lancer msn, thunderbird et mozilla en même temps, des difficultés parfois à se fermer, je suis alors obligée de tenir le bouton on/off appuyé ...
J'ai fait un hijack, le voici:
Logfile of HijackThis v1.99.1
Scan saved at 16:43:08, on 26/02/2008
Platform: Windows XP SP2 (WinNT 5.01.2600)
MSIE: Internet Explorer v6.00 SP2 (6.00.2900.2180)

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:\Program Files\Alwil Software\Avast4\aswUpdSv.exe
C:\Program Files\Alwil Software\Avast4\ashServ.exe
C:\WINDOWS\Explorer.EXE
C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
C:\Program Files\Club-Internet\Agent Wi-Fi V2.1\McciTrayApp.exe
C:\PROGRA~1\CLUB-I~1\LECOMP~1\SMARTB~1\MotiveSB.exe
C:\Program Files\CyberLink DVD Solution\PowerDVD\PDVDServ.exe
C:\Program Files\MSN Messenger\MsnMsgr.Exe
C:\Program Files\Google\GoogleToolbarNotifier\GoogleToolbarNotifier.exe
C:\WINDOWS\system32\spoolsv.exe
C:\Program Files\Belkin\Belkin Wireless Network Utility\WLService.exe
C:\WINDOWS\eHome\ehRecvr.exe
C:\Program Files\Belkin\Belkin Wireless Network Utility\WLanCfgG.exe
C:\Program Files\Club-Internet\Le Compagnon Club\bin\mpbtn.exe
C:\WINDOWS\eHome\ehSched.exe
C:\Program Files\Sunbelt Software\Personal Firewall\kpf4ss.exe
C:\WINDOWS\system32\o2flash.exe
C:\WINDOWS\system32\svchost.exe
C:\Program Files\Sunbelt Software\Personal Firewall\kpf4gui.exe
C:\Program Files\Alwil Software\Avast4\ashMaiSv.exe
C:\Program Files\Alwil Software\Avast4\ashWebSv.exe
C:\WINDOWS\system32\dllhost.exe
C:\Program Files\Sunbelt Software\Personal Firewall\kpf4gui.exe
C:\Program Files\MSN Messenger\usnsvc.exe
C:\WINDOWS\System32\svchost.exe
C:\Program Files\Mozilla Firefox\firefox.exe
C:\Program Files\WinRAR\WinRAR.exe
C:\DOCUME~1\Lol\LOCALS~1\Temp\Rar$EX00.735\HijackThis.exe

R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://www.google.fr/webhp?sourcei [...] r&ie=UTF-8
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = http://fr.yahoo.com/fsc/
R0 - HKLM\Software\Microsoft\Internet Explorer\Main,Start Page = http://fr.yahoo.com/fsc/
R1 - HKCU\Software\Microsoft\Internet Connection Wizard,ShellNext = http://fr.yahoo.com/fsc/
R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Window Title = Internet Explorer avec Club-Internet
R1 - HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings,ProxyOverride = 127.0.0.1
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Liens
O2 - BHO: Adobe PDF Reader Link Helper - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Program Files\Adobe\Acrobat 7.0\ActiveX\AcroIEHelper.dll
O2 - BHO: (no name) - {7E853D72-626A-48EC-A868-BA8D5E23E045} - (no file)
O2 - BHO: Windows Live Sign-in Helper - {9030D464-4C02-4ABF-8ECC-5164760863C6} - C:\Program Files\Fichiers communs\Microsoft Shared\Windows Live\WindowsLiveLogin.dll
O2 - BHO: Google Toolbar Helper - {AA58ED58-01DD-4d91-8333-CF10577473F7} - c:\program files\google\googletoolbar2.dll
O2 - BHO: Google Toolbar Notifier BHO - {AF69DE43-7D58-4638-B6FA-CE66B5AD205D} - C:\Program Files\Google\GoogleToolbarNotifier\2.0.301.7164\swg.dll
O3 - Toolbar: Easy-WebPrint - {327C2873-E90D-4c37-AA9D-10AC9BABA46C} - C:\Program Files\Canon\Easy-WebPrint\Toolband.dll
O3 - Toolbar: &Google - {2318C2B1-4965-11d4-9B18-009027A5CD4F} - c:\program files\google\googletoolbar2.dll
O4 - HKLM\..\Run: [avast!] C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
O4 - HKLM\..\Run: [REGSHAVE] C:\Program Files\REGSHAVE\REGSHAVE.EXE /AUTORUN
O4 - HKLM\..\Run: [Club-Internet_McciTrayApp] C:\Program Files\Club-Internet\Agent Wi-Fi V2.1\McciTrayApp.exe
O4 - HKLM\..\Run: [Motive SmartBridge] C:\PROGRA~1\CLUB-I~1\LECOMP~1\SMARTB~1\MotiveSB.exe
O4 - HKLM\..\Run: [RemoteControl] "C:\Program Files\CyberLink DVD Solution\PowerDVD\PDVDServ.exe"
O4 - HKCU\..\Run: [MsnMsgr] "C:\Program Files\MSN Messenger\MsnMsgr.Exe" /background
O4 - HKCU\..\Run: [swg] C:\Program Files\Google\GoogleToolbarNotifier\GoogleToolbarNotifier.exe
O4 - Global Startup: Lancement rapide d'Adobe Reader.lnk = C:\Program Files\Adobe\Acrobat 7.0\Reader\reader_sl.exe
O4 - Global Startup: LE COMPAGNON CLUB.lnk = C:\Program Files\Club-Internet\Le Compagnon Club\bin\matcli.exe
O8 - Extra context menu item: E&xport to Microsoft Excel - res://C:\PROGRA~1\MICROS~2\Office10\EXCEL.EXE/3000
O8 - Extra context menu item: Easy-WebPrint Ajouter à la liste d'impressions - res://C:\Program Files\Canon\Easy-WebPrint\Resource.dll/RC_AddToList.html
O8 - Extra context menu item: Easy-WebPrint Impression rapide - res://C:\Program Files\Canon\Easy-WebPrint\Resource.dll/RC_HSPrint.html
O8 - Extra context menu item: Easy-WebPrint Imprimer - res://C:\Program Files\Canon\Easy-WebPrint\Resource.dll/RC_Print.html
O8 - Extra context menu item: Easy-WebPrint Prévisualiser - res://C:\Program Files\Canon\Easy-WebPrint\Resource.dll/RC_Preview.html
O16 - DPF: {193C772A-87BE-4B19-A7BB-445B226FE9A1} (ewidoOnlineScan Control) - http://www.cyber-infos.net/files/OnlineScan.cab
O18 - Protocol: livecall - {828030A1-22C1-4009-854F-8E305202313F} - C:\PROGRA~1\MSNMES~1\MSGRAP~1.DLL
O18 - Protocol: msnim - {828030A1-22C1-4009-854F-8E305202313F} - C:\PROGRA~1\MSNMES~1\MSGRAP~1.DLL
O20 - Winlogon Notify: igfxcui - C:\WINDOWS\SYSTEM32\igfxdev.dll
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 - Unknown owner - C:\Program Files\Alwil Software\Avast4\ashMaiSv.exe" /service (file missing)
O23 - Service: avast! Web Scanner - Unknown owner - C:\Program Files\Alwil Software\Avast4\ashWebSv.exe" /service (file missing)
O23 - Service: Belkin Wireless USB Network Adapter (Belkin Wireless USB Network Adapter Service) - Unknown owner - C:\Program Files\Belkin\Belkin Wireless Network Utility\WLService.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\1050\Intel 32\IDriverT.exe
O23 - Service: Sunbelt Kerio Personal Firewall 4 (KPF4) - Sunbelt Software - C:\Program Files\Sunbelt Software\Personal Firewall\kpf4ss.exe
O23 - Service: O2Micro Flash Memory (O2Flash) - Unknown owner - C:\WINDOWS\system32\o2flash.exe

Merci d'avance

Merci pour l'analyse...
Qu'est-ce qui pourrait ralentir mon pc?
Nécessite-t-il une défragmentation?