Ordinateur lent

Bonjour,

Mon ordinateur sous XP est très lent. J'ai lancé hijack this et voici le resultat du scan :
Que dois-je faire maintenant ?

Logfile of Trend Micro HijackThis v2.0.5
Scan saved at 14:29:06, on 24/10/2014
Platform: Windows XP SP3 (WinNT 5.01.2600)
MSIE: Internet Explorer v8.00 (8.00.6001.18702)

FIREFOX: 32.0.3 (x86 fr)
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\Ati2evxx.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\System32\svchost.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\system32\Ati2evxx.exe
C:\Program Files\AVAST Software\Avast\AvastSvc.exe
C:\WINDOWS\Explorer.EXE
C:\WINDOWS\system32\spoolsv.exe
C:\WINDOWS\SMINST\Scheduler.exe
C:\WINDOWS\vsnp2uvc.exe
C:\Program Files\AVAST Software\Avast\avastUI.exe
C:\WINDOWS\system32\ctfmon.exe
C:\Program Files\Skype\Phone\Skype.exe
C:\Program Files\Fichiers communs\InterVideo\RegMgr\iviRegMgr.exe
C:\Program Files\PDF Complete\pdfsvc.exe
C:\WINDOWS\system32\HPZipm12.exe
C:\WINDOWS\system32\svchost.exe
C:\Program Files\Malwarebytes Anti-Malware\mbam.exe
C:\Program Files\Mozilla Firefox\firefox.exe
C:\Documents and Settings\Administrateur.HP_COMPAQ\Mes documents\Téléchargements\HijackThis.exe

R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = https://www.google.com/?hl=fr&gws_rd=ssl
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = http://go.microsoft.com/fwlink/?LinkId=69157
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://go.microsoft.com/fwlink/?LinkId=69157
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: SSVHelper Class - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Program Files\Java\jre1.6.0_04\bin\ssv.dll
O2 - BHO: avast! Online Security - {8E5E2654-AD2D-48bf-AC2D-D17F00898D06} - C:\Program Files\AVAST Software\Avast\aswWebRepIE.dll
O3 - Toolbar: avast! Online Security - {8E5E2654-AD2D-48bf-AC2D-D17F00898D06} - C:\Program Files\AVAST Software\Avast\aswWebRepIE.dll
O4 - HKLM\..\Run: [avast] "C:\Program Files\AVAST Software\Avast\avastUI.exe" /nogui
O4 - HKLM\..\Run: [MSConfig] C:\WINDOWS\PCHealth\HelpCtr\Binaries\MSConfig.exe /auto
O4 - HKUS\S-1-5-18-{ED1FC765-E35E-4C3D-BF15-2C2B11260CE4}-0\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User '?')
O4 - HKUS\S-1-5-19\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'SERVICE LOCAL')
O4 - HKUS\S-1-5-19-{ED1FC765-E35E-4C3D-BF15-2C2B11260CE4}-0\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User '?')
O4 - HKUS\S-1-5-20\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'SERVICE RÉSEAU')
O4 - HKUS\S-1-5-20-{ED1FC765-E35E-4C3D-BF15-2C2B11260CE4}-0\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User '?')
O4 - HKUS\S-1-5-21-2073810329-191791083-3001908232-500-{ED1FC765-E35E-4C3D-BF15-2C2B11260CE4}-0\..\Run: [ctfmon.exe] C:\WINDOWS\system32\ctfmon.exe (User '?')
O4 - HKUS\S-1-5-18\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'SYSTEM')
O4 - HKUS\.DEFAULT\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'Default user')
O8 - Extra context menu item: &Search - http://buttons.allin1convert.com/one-toolbaredits/menusearch.jhtml?s=211827548&p2=^AYY^xdm073^YYA^fr&si=flvrunner&a=75D1E2A1-9C53-49B8-B42B-11F47CA5AAAE&n=2013100611
O9 - Extra button: (no name) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.6.0_04\bin\ssv.dll
O9 - Extra 'Tools' menuitem: Console Java (Sun) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.6.0_04\bin\ssv.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
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
O14 - IERESET.INF: START_PAGE_URL=http://www.hp.com
O16 - DPF: {05D96F71-87C6-11D3-9BE4-00902742D6E0} (Lotus Quickr Class) - http://qr8.orion.education.fr/qp2.cab
O16 - DPF: {D27CDB6E-AE6D-11CF-96B8-444553540000} (Shockwave Flash Object) - http://fpdownload2.macromedia.com/get/shockwave/cabs/flash/swflash.cab
O18 - Protocol: skype4com - {FFC8B962-9B40-4DFF-9458-1830C7DD7F5D} - C:\PROGRA~1\FICHIE~1\Skype\SKYPE4~1.DLL
O20 - Winlogon Notify: GoToAssist - C:\Program Files\Citrix\GoToAssist\830\G2AWinLogon.dll
O22 - SharedTaskScheduler: Pré-chargeur Browseui - {438755C2-A8BA-11D1-B96B-00A0C90312E1} - C:\WINDOWS\system32\browseui.dll
O22 - SharedTaskScheduler: Démon de cache des catégories de composant - {8C7461EF-2B13-11d2-BE35-3078302C2030} - C:\WINDOWS\system32\browseui.dll
O23 - Service: Adobe Flash Player Update Service (AdobeFlashPlayerUpdateSvc) - Adobe Systems Incorporated - C:\WINDOWS\system32\Macromed\Flash\FlashPlayerUpdateService.exe
O23 - Service: Ati HotKey Poller - ATI Technologies Inc. - C:\WINDOWS\system32\Ati2evxx.exe
O23 - Service: avast! Antivirus - AVAST Software - C:\Program Files\AVAST Software\Avast\AvastSvc.exe
O23 - Service: Service d'administration du Gestionnaire de disque logique (dmadmin) - Unknown owner - C:\WINDOWS\System32\dmadmin.exe
O23 - Service: Journal des événements (Eventlog) - Unknown owner - C:\WINDOWS\system32\services.exe
O23 - Service: GoToAssist - Citrix Online, a division of Citrix Systems, Inc. - C:\Program Files\Citrix\GoToAssist\830\g2aservice.exe
O23 - Service: Service Google Update (gupdate) (gupdate) - Unknown owner - C:\Program Files\Google\Update\GoogleUpdate.exe
O23 - Service: Service Google Update (gupdatem) (gupdatem) - Unknown owner - C:\Program Files\Google\Update\GoogleUpdate.exe
O23 - Service: Google Software Updater (gusvc) - Google - C:\Program Files\Google\Common\Google Updater\GoogleUpdaterService.exe
O23 - Service: Service COM de gravage de CD IMAPI (ImapiService) - Unknown owner - C:\WINDOWS\system32\imapi.exe
O23 - Service: IviRegMgr - InterVideo - C:\Program Files\Fichiers communs\InterVideo\RegMgr\iviRegMgr.exe
O23 - Service: Partage de Bureau à distance NetMeeting (mnmsrvc) - Unknown owner - C:\WINDOWS\system32\mnmsrvc.exe
O23 - Service: Mozilla Maintenance Service (MozillaMaintenance) - Mozilla Foundation - C:\Program Files\Mozilla Maintenance Service\maintenanceservice.exe
O23 - Service: PC Angel (PCA) - SoftThinks - C:\WINDOWS\SMINST\PCAngel.exe
O23 - Service: PDF Document Manager (pdfcDispatcher) - PDF Complete Inc - C:\Program Files\PDF Complete\pdfsvc.exe
O23 - Service: Plug-and-Play (PlugPlay) - Unknown owner - C:\WINDOWS\system32\services.exe
O23 - Service: Pml Driver HPZ12 - HP - C:\WINDOWS\system32\HPZipm12.exe
O23 - Service: Gestionnaire de session d'aide sur le Bureau à distance (RDSessMgr) - Unknown owner - C:\WINDOWS\system32\sessmgr.exe
O23 - Service: Carte à puce (SCardSvr) - Unknown owner - C:\WINDOWS\System32\SCardSvr.exe
O23 - Service: Journaux et alertes de performance (SysmonLog) - Unknown owner - C:\WINDOWS\system32\smlogsvc.exe
O23 - Service: Cliché instantané de volume (VSS) - Unknown owner - C:\WINDOWS\System32\vssvc.exe
O23 - Service: Carte de performance WMI (WmiApSrv) - Unknown owner - C:\WINDOWS\system32\wbem\wmiapsrv.exe
O23 - Service: Service Partage réseau du Lecteur Windows Media (WMPNetworkSvc) - Unknown owner - C:\Program Files\Windows Media Player\WMPNetwk.exe