Sasser Worm?

Someone please help me. My computer keeps restarting unexpectedly, often with a textbox saying lsass.exe has been terminated unexpectedly, and counting down from 1 minute the computer shuts down. I tried running spybot, mcafee antivirus, and others but they all shut down unexpectedly while scanning. Spybot was in the midst of catching something when it shut down....now when itry running it an error message says "this application has been changed, check for viruses instantly!"

I suspect some type of worm,...someone please help.
Logfile of HijackThis v1.99.1
Scan saved at 10:39:09 AM, on 1/21/2007
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:\WINDOWS\Explorer.EXE
C:\Program Files\Internet Explorer\IEXPLORE.EXE
C:\Program Files\Opera\Opera.exe
C:\Documents and Settings\Owner.ITA\Desktop\hijackthis\HijackThis.exe

R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Bar = http://www.gateway.com/g/sidepanel.html?Ch=Retail&Br=GTW&Loc=ENG_US&Sys=DTP&M=GT4024
R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://www.gateway.com/g/startpage.html?Ch=Retail&Br=GTW&Loc=ENG_US&Sys=DTP&M=GT4024
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = http://www.gateway.com/g/startpage.html?Ch=Retail&Br=GTW&Loc=ENG_US&Sys=DTP&M=GT4024
R0 - HKLM\Software\Microsoft\Internet Explorer\Main,Start Page = http://www.gateway.com/g/startpage.html?Ch=Retail&Br=GTW&Loc=ENG_US&Sys=DTP&M=GT4024
R0 - HKLM\Software\Microsoft\Internet Explorer\Search,SearchAssistant = http://www.gateway.com/g/sidepanel.html?Ch=Retail&Br=GTW&Loc=ENG_US&Sys=DTP&M=GT4024
R1 - HKCU\Software\Microsoft\Internet Connection Wizard,ShellNext = http://www.gateway.com/g/startpage.html?Ch=Retail&Br=GTW&Loc=ENG_US&Sys=DTP&M=GT4024
O2 - BHO: AcroIEHlprObj Class - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Program Files\Adobe\Acrobat 7.0\ActiveX\AcroIEHelper.dll
O2 - BHO: McAfee AntiPhishing Filter - {41D68ED8-4CFF-4115-88A6-6EBB8AF19000} - c:\program files\mcafee\spamkiller\mcapfbho.dll
O2 - BHO: (no name) - {53707962-6F74-2D53-2644-206D7942484F} - C:\Program Files\Spybot - Search & Destroy\SDHelper.dll
O2 - BHO: Google Toolbar Helper - {AA58ED58-01DD-4d91-8333-CF10577473F7} - c:\program files\google\googletoolbar2.dll
O2 - BHO: Browser Address Error Redirector - {CA6319C0-31B7-401E-A518-A07C3DB8F777} - c:\windows\system32\BAE.dll
O3 - Toolbar: McAfee VirusScan - {BA52B914-B692-46c4-B683-905236F6F655} - c:\progra~1\mcafee.com\vso\mcvsshl.dll
O3 - Toolbar: &Google - {2318C2B1-4965-11d4-9B18-009027A5CD4F} - c:\program files\google\googletoolbar2.dll
O4 - HKLM\..\Run: [MSConfig] C:\WINDOWS\PCHealth\HelpCtr\Binaries\MSConfig.exe /auto
O4 - HKLM\..\Run: [KernelFaultCheck] %systemroot%\system32\dumprep 0 -k
O4 - HKLM\..\Run: [MCUpdateExe] c:\PROGRA~1\mcafee.com\agent\mcupdate.exe
O4 - HKLM\..\Run: [MCAgentExe] c:\PROGRA~1\mcafee.com\agent\McAgent.exe
O4 - HKLM\..\Run: [MSKAGENTEXE] C:\PROGRA~1\McAfee\SPAMKI~1\MskAgent.exe
O8 - Extra context menu item: E&xport to Microsoft Excel - res://C:\PROGRA~1\MICROS~2\OFFICE11\EXCEL.EXE/3000
O9 - Extra button: (no name) - {39FD89BF-D3F1-45b6-BB56-3582CCF489E1} - c:\program files\mcafee\spamkiller\mcapfbho.dll
O9 - Extra 'Tools' menuitem: McAfee AntiPhishing Filter - {39FD89BF-D3F1-45b6-BB56-3582CCF489E1} - c:\program files\mcafee\spamkiller\mcapfbho.dll
O9 - Extra button: Real.com - {CD67F990-D8E9-11d2-98FE-00C0F0318AFE} - C:\WINDOWS\system32\Shdocvw.dll
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
O20 - AppInit_DLLs: C:\PROGRA~1\Google\GOOGLE~1\GOEC62~1.DLL
O23 - Service: Ati HotKey Poller - ATI Technologies Inc. - C:\WINDOWS\system32\Ati2evxx.exe
O23 - Service: McAfee WSC Integration (McDetect.exe) - McAfee, Inc - c:\program files\mcafee.com\agent\mcdetect.exe
O23 - Service: McAfee.com McShield (McShield) - McAfee Inc. - c:\PROGRA~1\mcafee.com\vso\mcshield.exe
O23 - Service: McAfee Task Scheduler (McTskshd.exe) - McAfee, Inc - c:\PROGRA~1\mcafee.com\agent\mctskshd.exe
O23 - Service: McAfee SecurityCenter Update Manager (mcupdmgr.exe) - McAfee, Inc - C:\PROGRA~1\McAfee.com\Agent\mcupdmgr.exe
O23 - Service: McAfee Personal Firewall Service (MpfService) - McAfee Corporation - C:\PROGRA~1\McAfee.com\PERSON~1\MpfService.exe
O23 - Service: McAfee SpamKiller Server (MskService) - McAfee Inc. - C:\PROGRA~1\McAfee\SPAMKI~1\MSKSrvr.exe
O23 - Service: PrismXL - New Boundary Technologies, Inc. - C:\Program Files\Common Files\New Boundary\PrismXL\PRISMXL.SYS