My PC will turn itself of when IM running a scan or running a full window programme, i just can't seem to fix it. Has anyone GOT any ideas? Here is the log of hijack this if this will help:

Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 11:24:12, on 04/03/2009
Platform: WINDOWS XP SP3 (WinNT 5.01.2600)
MSIE: Internet Explorer v7.00 (7.00.6000.16791)
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\system32\spoolsv.exe
C:\WINDOWS\Explorer.EXE
C:\Program Files\Common Files\Apple\Mobile Device Support\bin\AppleMobileDeviceService.exe
C:\PROGRA~1\AVG\AVG8\avgwdsvc.exe
C:\Program Files\Bonjour\mDNSResponder.exe
C:\Program Files\Kontiki\KService.exe
C:\WINDOWS\System32\svchost.exe
C:\WINDOWS\vsnp2uvc.exe
C:\WINDOWS\RTHDCPL.EXE
C:\PROGRA~1\AVG\AVG8\avgemc.exe
C:\PROGRA~1\AVG\AVG8\avgrsx.exe
C:\PROGRA~1\AVG\AVG8\avgnsx.exe
C:\PROGRA~1\BTHOME~1\Help\SMARTB~1\BTHelpNotifier.exe
C:\Program Files\btbb_wcm\McciTrayApp.exe
C:\Program Files\iTunes\iTunesHelper.exe
C:\PROGRA~1\Yahoo!\browser\ycommon.exe
C:\PROGRA~1\AVG\AVG8\avgtray.exe
C:\Program Files\Windows Live\Messenger\MsnMsgr.Exe
C:\WINDOWS\system32\ctfmon.exe
C:\Program Files\AVG\AVG8\avgcsrvx.exe
C:\Program Files\iPod\bin\iPodService.exe
C:\Program Files\Internet Explorer\iexplore.exe
C:\Program Files\AVG\AVG8\aAvgApi.exe
C:\WINDOWS\system32\rundll32.exe
C:\Program Files\Windows Live\Messenger\usnsvc.exe
C:\Program Files\Trend Micro\HijackThis\HijackThis.exe

R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Bar = http://uk.red.clientapps.yahoo.com/customize/btyahoo/defaults/sb/*http://uk.docs.yahoo.com/info/bt_side.html
R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Page = http://uk.red.clientapps.yahoo.com/customize/btyahoo/defaults/sp/*http://uk.search.yahoo.com/
R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://www.google.co.uk/
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://uk.red.clientapps.yahoo.com/customize/btyahoo/defaults/su/*http://uk.search.yahoo.com/
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Search Bar = http://uk.red.clientapps.yahoo.com/customize/btyahoo/defaults/sb/*http://uk.docs.yahoo.com/info/bt_side.html
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Search Page = http://uk.red.clientapps.yahoo.com/customize/btyahoo/defaults/sp/*http://uk.search.yahoo.com/
R0 - HKLM\Software\Microsoft\Internet Explorer\Main,Start Page = http://go.microsoft.com/fwlink/?LinkId=69157
R0 - HKLM\Software\Microsoft\Internet Explorer\Search,SearchAssistant =
R0 - HKLM\Software\Microsoft\Internet Explorer\Search,CustomizeSearch =
R1 - HKCU\Software\Microsoft\Internet Explorer\SearchURL,(Default) = http://uk.red.clientapps.yahoo.com/customize/btyahoo/defaults/su/*http://uk.search.yahoo.com/
R1 - HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings,ProxyOverride = 127.0.0.1;*.local
O2 - BHO: Yahoo! Toolbar Helper - {02478D38-C3F9-4EFB-9B51-7695ECA05670} - C:\Program Files\Yahoo!\Companion\Installs\cpn\yt.dll
O2 - BHO: WormRadar.com IESiteBlocker.NavFilter - {3CA2F312-6F6E-4B53-A66E-4E65E497C8C0} - C:\Program Files\AVG\AVG8\avgssie.dll
O2 - BHO: UberButton Class - {5BAB4B5B-68BC-4B02-94D6-2FC0DE4A7897} - C:\Program Files\Yahoo!\Common\yiesrvc.dll
O2 - BHO: YahooTaggedBM Class - {65D886A2-7CA7-479B-BB95-14D1EFB7946A} - C:\Program Files\Yahoo!\Common\YIeTagBm.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\Common Files\Microsoft Shared\Windows Live\WindowsLiveLogin.dll
O2 - BHO: AVG Security Toolbar - {A057A204-BACC-4D26-9990-79A187E2698E} - C:\PROGRA~1\AVG\AVG8\AVGTOO~1.DLL
O2 - BHO: SidebarAutoLaunch Class - {F2AA9440-6328-4933-B7C9-A6CCDF9CBF6D} - C:\Program Files\Yahoo!\browser\YSidebarIEBHO.dll
O3 - Toolbar: Yahoo! Toolbar - {EF99BD32-C1FB-11D2-892F-0090271D4F88} - C:\Program Files\Yahoo!\Companion\Installs\cpn\yt.dll
O3 - Toolbar: AVG Security Toolbar - {A057A204-BACC-4D26-9990-79A187E2698E} - C:\PROGRA~1\AVG\AVG8\AVGTOO~1.DLL
O4 - HKLM\..\Run: [snp2uvc] C:\WINDOWS\vsnp2uvc.exe
O4 - HKLM\..\Run: [RTHDCPL] RTHDCPL.EXE
O4 - HKLM\..\Run: [Alcmtr] ALCMTR.EXE
O4 - HKLM\..\Run: [MOTIVE SmartBridge] C:\PROGRA~1\BTHOME~1\Help\SMARTB~1\BTHelpNotifier.exe
O4 - HKLM\..\Run: [btbb_wcm_McciTrayApp] C:\Program Files\btbb_wcm\McciTrayApp.exe
O4 - HKLM\..\Run: [YBrowser] C:\PROGRA~1\Yahoo!\browser\ybrwicon.exe
O4 - HKLM\..\Run: [4oD] "C:\Program Files\Kontiki\KHost.exe" -all
O4 - HKLM\..\Run: [QuickTime Task] "C:\Program Files\QuickTime\qttask.exe" -atboottime
O4 - HKLM\..\Run: [iTunesHelper] "C:\Program Files\iTunes\iTunesHelper.exe"
O4 - HKLM\..\Run: [AVG8_TRAY] C:\PROGRA~1\AVG\AVG8\avgtray.exe
O4 - HKCU\..\Run: [MsnMsgr] "C:\Program Files\Windows Live\Messenger\MsnMsgr.Exe" /background
O4 - HKCU\..\Run: [ctfmon.exe] C:\WINDOWS\system32\ctfmon.exe
O4 - HKCU\..\Run: [Yahoo! Pager] C:\PROGRA~1\Yahoo!\MESSEN~1\ypager.exe -quiet
O4 - HKCU\..\Run: [eyeBeam SIP Client] "C:\Program Files\BT Broadband Talk Softphone\BTSoftphone.exe"
O4 - HKCU\..\Run: [kdx] C:\Program Files\Kontiki\KHost.exe -all
O4 - Global Startup: BT Broadband Desktop Help.lnk = C:\Program Files\BT Home Hub\Help\bin\matcli.exe
O9 - Extra button: BT Yahoo! Services - {5BAB4B5B-68BC-4B02-94D6-2FC0DE4A7897} - C:\Program Files\Yahoo!\Common\yiesrvc.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
O16 - DPF: {30528230-99f7-4bb4-88d8-fa1d4f56a2ab} (YInstStarter Class) - C:\Program Files\Yahoo!\common\yinsthelper.dll
O16 - DPF: {6414512B-B978-451D-A0D8-FCFDF33E833C} (WUWebControl Class) - http://www.update.microsoft.com/windowsupdate/v6/V5Controls/en/x86/client/wuweb_site.cab?1229226114132
O16 - DPF: {C3F79A2B-B9B4-4A66-B012-3EE46475B072} (MessengerStatsClient Class) - http://messenger.zone.msn.com/binary/MessengerStatsPAClient.cab56907.cab
O18 - Protocol: linkscanner - {F274614C-63F8-47D5-A4D1-FBDDE494F8D1} - C:\Program Files\AVG\AVG8\avgpp.dll
O20 - Winlogon Notify: avgrsstarter - C:\WINDOWS\SYSTEM32\avgrsstx.dll
O23 - Service: Apple Mobile Device - Apple Inc. - C:\Program Files\Common Files\Apple\Mobile Device Support\bin\AppleMobileDeviceService.exe
O23 - Service: AVG Free8 E-mail Scanner (avg8emc) - AVG Technologies CZ, s.r.o. - C:\PROGRA~1\AVG\AVG8\avgemc.exe
O23 - Service: AVG Free8 WatchDog (avg8wd) - AVG Technologies CZ, s.r.o. - C:\PROGRA~1\AVG\AVG8\avgwdsvc.exe
O23 - Service: Bonjour Service - Apple Inc. - C:\Program Files\Bonjour\mDNSResponder.exe
O23 - Service: iPod Service - Apple Inc. - C:\Program Files\iPod\bin\iPodService.exe
O23 - Service: KService - Kontiki Inc. - C:\Program Files\Kontiki\KService.exe
O23 - Service: YPCService - Yahoo! Inc. - C:\WINDOWS\system32\YPCSER~1.EXE

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