Pc fechando programas e desligando sozinho

meu Pc tá fechando programas e desligando sozinho...tenho quase certeza que é vírus. segue o log abaixo:

Logfile of Trend Micro HijackThis v2.0.4
Scan saved at 14:27:52, on 26/1/2011
Platform: Windows XP SP3 (WinNT 5.01.2600)
MSIE: Internet Explorer v8.00 (8.00.6001.18702)
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\svchost.exe
C:\Arquivos de programas\AVG\AVG9\avgchsvx.exe
C:\Arquivos de programas\AVG\AVG9\avgrsx.exe
C:\Arquivos de programas\AVG\AVG9\avgcsrvx.exe
C:\WINDOWS\Explorer.EXE
C:\WINDOWS\system32\spoolsv.exe
C:\WINDOWS\system32\RunDll32.exe
C:\ARQUIV~1\AVG\AVG9\avgtray.exe
C:\WINDOWS\AGRSMMSG.exe
C:\Arquivos de programas\Arquivos comuns\Java\Java Update\jusched.exe
C:\Arquivos de programas\Adobe\Reader 9.0\Reader\Reader_sl.exe
C:\Arquivos de programas\AVG\AVG9\avgwdsvc.exe
C:\Arquivos de programas\Arquivos comuns\Real\Update_OB\realsched.exe
C:\WINDOWS\system32\ctfmon.exe
C:\Arquivos de programas\Messenger\msmsgs.exe
C:\Arquivos de programas\Java\jre6\bin\jqs.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\system32\wuauclt.exe
C:\WINDOWS\system32\wbem\wmiapsrv.exe
C:\Arquivos de programas\AVG\AVG9\avgnsx.exe
C:\Arquivos de programas\Mozilla Firefox\firefox.exe
C:\WINDOWS\System32\svchost.exe
C:\Arquivos de programas\Mozilla Firefox\plugin-container.exe
C:\HiJackThis.exe

R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Page = http://search.localstrike.com.ar/
R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://search.localstrike.com.ar/
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = http://search.localstrike.com.ar/
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Search_URL = http://search.localstrike.com.ar/
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Search Page = http://search.localstrike.com.ar/
R0 - HKLM\Software\Microsoft\Internet Explorer\Main,Start Page = http://search.localstrike.com.ar/
O2 - BHO: AcroIEHelperStub - {18DF081C-E8AD-4283-A596-FA578C2EBDC3} - C:\Arquivos de programas\Arquivos comuns\Adobe\Acrobat\ActiveX\AcroIEHelperShim.dll
O2 - BHO: RealPlayer Download and Record Plugin for Internet Explorer - {3049C3E9-B461-4BC5-8870-4C09146192CA} - C:\Documents and Settings\All Users\Dados de aplicativos\Real\RealPlayer\BrowserRecordPlugin\IE\rpbrowserrecordplugin.dll
O2 - BHO: WormRadar.com IESiteBlocker.NavFilter - {3CA2F312-6F6E-4B53-A66E-4E65E497C8C0} - C:\Arquivos de programas\AVG\AVG9\avgssie.dll
O2 - BHO: (no name) - {5C255C8A-E604-49b4-9D64-90988571CECB} - (no file)
O2 - BHO: Auxiliar de Conexão do Windows Live - {9030D464-4C02-4ABF-8ECC-5164760863C6} - C:\Arquivos de programas\Arquivos comuns\Microsoft Shared\Windows Live\WindowsLiveLogin.dll
O2 - BHO: Ask Toolbar BHO - {D4027C7F-154A-4066-A1AD-4243D8127440} - C:\Arquivos de programas\Ask.com\GenericAskToolbar.dll
O2 - BHO: Java(tm) Plug-In 2 SSV Helper - {DBC80044-A445-435b-BC74-9C25C1C588A9} - C:\Arquivos de programas\Java\jre6\bin\jp2ssv.dll
O2 - BHO: JQSIEStartDetectorImpl - {E7E6F031-17CE-4C07-BC86-EABFE594F69C} - C:\Arquivos de programas\Java\jre6\lib\deploy\jqs\ie\jqs_plugin.dll
O3 - Toolbar: Ask Toolbar - {D4027C7F-154A-4066-A1AD-4243D8127440} - C:\Arquivos de programas\Ask.com\GenericAskToolbar.dll
O4 - HKLM\..\Run: [Cmaudio] RunDll32 cmicnfg.cpl,CMICtrlWnd
O4 - HKLM\..\Run: [SiSPower] Rundll32.exe SiSPower.dll,ModeAgent
O4 - HKLM\..\Run: [AVG9_TRAY] C:\ARQUIV~1\AVG\AVG9\avgtray.exe
O4 - HKLM\..\Run: [AGRSMMSG] AGRSMMSG.exe
O4 - HKLM\..\Run: [SunJavaUpdateSched] "C:\Arquivos de programas\Arquivos comuns\Java\Java Update\jusched.exe"
O4 - HKLM\..\Run: [KernelFaultCheck] %systemroot%\system32\dumprep 0 -k
O4 - HKLM\..\Run: [Adobe Reader Speed Launcher] "C:\Arquivos de programas\Adobe\Reader 9.0\Reader\Reader_sl.exe"
O4 - HKLM\..\Run: [Adobe ARM] "C:\Arquivos de programas\Arquivos comuns\Adobe\ARM\1.0\AdobeARM.exe"
O4 - HKLM\..\Run: [QuickTime Task] "C:\Arquivos de programas\QuickTime\qttask.exe" -atboottime
O4 - HKLM\..\Run: [TkBellExe] "C:\Arquivos de programas\Arquivos comuns\Real\Update_OB\realsched.exe" -osboot
O4 - HKCU\..\Run: [ctfmon.exe] C:\WINDOWS\system32\ctfmon.exe
O4 - HKCU\..\Run: [MSMSGS] "C:\Arquivos de programas\Messenger\msmsgs.exe" /background
O4 - HKUS\S-1-5-19\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'LOCAL SERVICE')
O4 - HKUS\S-1-5-20\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'NETWORK SERVICE')
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: E&xportar para o Microsoft Excel - res://C:\ARQUIV~1\MICROS~2\OFFICE11\EXCEL.EXE/3000
O9 - Extra button: Pesquisar - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\ARQUIV~1\MICROS~2\OFFICE11\REFIEBAR.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:\Arquivos de programas\Messenger\msmsgs.exe
O9 - Extra 'Tools' menuitem: Windows Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\Arquivos de programas\Messenger\msmsgs.exe
O14 - IERESET.INF: SEARCH_PAGE_URL=&http://home.microsoft.com/intl/br/access/allinone.asp
O16 - DPF: {149E45D8-163E-4189-86FC-45022AB2B6C9} (SpinTop DRM Control) - file:///C:/Arquivos%20de%20programas/Dream%20Day%20First%20Home/Images/stg_drm.ocx
O16 - DPF: {CC450D71-CC90-424C-8638-1F2DBAC87A54} (ArmHelper Control) - file:///C:/Arquivos%20de%20programas/Dream%20Day%20First%20Home/Images/armhelper.ocx
O18 - Protocol: linkscanner - {F274614C-63F8-47D5-A4D1-FBDDE494F8D1} - C:\Arquivos de programas\AVG\AVG9\avgpp.dll
O20 - Winlogon Notify: avgrsstarter - avgrsstx.dll (file missing)
O22 - SharedTaskScheduler: Pré-carregador Browseui - {438755C2-A8BA-11D1-B96B-00A0C90312E1} - C:\WINDOWS\system32\browseui.dll
O22 - SharedTaskScheduler: Daemon de cache de categorias de componente - {8C7461EF-2B13-11d2-BE35-3078302C2030} - C:\WINDOWS\system32\browseui.dll
O23 - Service: AVG Free WatchDog (avg9wd) - AVG Technologies CZ, s.r.o. - C:\Arquivos de programas\AVG\AVG9\avgwdsvc.exe
O23 - Service: Java Quick Starter (JavaQuickStarterService) - Sun Microsystems, Inc. - C:\Arquivos de programas\Java\jre6\bin\jqs.exe
O23 - Service: nProtect GameGuard Service (npggsvc) - Nokia - (no file)

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