Hijackthis log + CPU @ 100%

hi all, my problem: My cpu is running at 100% constantly, the task manager reports the process eating all the cpu as "system". Even from starting up it lags! Waiting for the login window used to be quick ( system is 1 week old!! ) and has slowed dramatically. I did norton antivirus sweep last night with september definitions. Computer is laggy now, help ?!
Logfile of HijackThis v1.98.2
Scan saved at 20:22:11, on 02/09/2004
Platform: Windows 2000 SP4 (WinNT 5.00.2195)
MSIE: Internet Explorer v6.00 SP1 (6.00.2800.1106)

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:\Program Files\Common Files\Symantec Shared\ccSetMgr.exe
C:\Program Files\Common Files\Symantec Shared\ccEvtMgr.exe
C:\WINDOWS\system32\spoolsv.exe
C:\WINDOWS\System32\svchost.exe
C:\Program Files\Norton SystemWorks\Norton Antivirus\navapsvc.exe
C:\WINDOWS\system32\regsvc.exe
C:\Program Files\Norton SystemWorks\Norton Antivirus\SAVScan.exe
C:\WINDOWS\system32\MSTask.exe
C:\Program Files\Common Files\Symantec Shared\CCPD-LC\symlcsvc.exe
C:\WINDOWS\System32\WBEM\WinMgmt.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\Explorer.EXE
C:\Program Files\Symantec\LiveUpdate\NDETECT.EXE
C:\PROGRA~1\PopOops\PopOops.exe
C:\Program Files\Common Files\Symantec Shared\ccApp.exe
C:\Program Files\Common Files\Symantec Shared\Security Center\UsrPrmpt.exe
C:\WINDOWS\system32\internat.exe
C:\Documents and Settings\All Users\Desktop\HijackThis.exe

R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Search Bar = http://red.clientapps.yahoo.com/customize/ie/defaults/sb/ymsgr/*http://www.yahoo.com/ext/search/search.html
R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Local Page =
R0 - HKLM\Software\Microsoft\Internet Explorer\Main,Local Page =
O2 - BHO: NAV Helper - {BDF3E430-B101-42AD-A544-FADC6B084872} - C:\Program Files\Norton SystemWorks\Norton Antivirus\NavShExt.dll
O3 - Toolbar: &Radio - {8E718888-423F-11D2-876E-00A0C9082467} - C:\WINDOWS\System32\msdxm.ocx
O3 - Toolbar: Norton AntiVirus - {42CDD1BF-3FFB-4238-8AD1-7859DF00B1D6} - C:\Program Files\Norton SystemWorks\Norton Antivirus\NavShExt.dll
O4 - HKLM\..\Run: [SoundMan] SOUNDMAN.EXE
O4 - HKLM\..\Run: [nwiz] nwiz.exe /install
O4 - HKLM\..\Run: [IntelliType] "C:\Program Files\Microsoft Hardware\Keyboard\type32.exe"
O4 - HKLM\..\Run: [KernelFaultCheck] %systemroot%\system32\dumprep 0 -k
O4 - HKLM\..\Run: [POINTER] C:\Program Files\Microsoft Hardware\Mouse\point32.exe
O4 - HKLM\..\Run: [Synchronization Manager] mobsync.exe /logon
O4 - HKLM\..\Run: [PopOops] C:\PROGRA~1\PopOops\PopOops.exe
O4 - HKLM\..\Run: [IgfxTray] C:\WINDOWS\system32\igfxtray.exe
O4 - HKLM\..\Run: [ccApp] "C:\Program Files\Common Files\Symantec Shared\ccApp.exe"
O4 - HKLM\..\Run: [SSC_UserPrompt] C:\Program Files\Common Files\Symantec Shared\Security Center\UsrPrmpt.exe
O4 - HKCU\..\Run: [CursorXP] C:\Program Files\CursorXP\CursorXP.exe
O4 - HKCU\..\Run: [internat.exe] internat.exe
O8 - Extra context menu item: Open in New &Window (PopOops) - C:\WINDOWS\Web\PopOops.htm
O9 - Extra button: Research - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\PROGRA~1\MICROS~2\OFFICE11\REFIEBAR.DLL
O16 - DPF: {2BC66F54-93A8-11D3-BEB6-00105AA9B6AE} (Symantec AntiVirus scanner) - http://security.symantec.com/sscv6/SharedContent/vc/bin/AvSniff.cab
O16 - DPF: {644E432F-49D3-41A1-8DD5-E099162EEEC5} (Symantec RuFSI Utility Class) - http://security.symantec.com/sscv6/SharedContent/common/bin/cabsa.cab
O16 - DPF: {70BA88C8-DAE8-4CE9-92BB-979C4A75F53B} (GSDACtl Class) - http://launch.gamespyarcade.com/software/launch/alaunch.cab
O16 - DPF: {E5D419D6-A846-4514-9FAD-97E826C84822} - http://fdl.msn.com/zone/datafiles/heartbeat.cab

just read here http://www.liutilities.com/products/wintaskspro/processlibrary/systemexe/ that system is a trojan is this true, l always thought it a system process no?!