Can someone please help me; how to remove this Trojan/virus fake warning popup:

"Some dangerous viruses detected in your system. Microsoft Window XP files corrupted. This may lead to the destruction of important files in F:\Windows. Download protection software now!

Click OK to download the antispyware. (Recommended)"

Here is the report from HijackThis:

Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 5:22:37 PM, on 2008-11-10
Platform: Windows XP SP3 (WinNT 5.01.2600)
MSIE: Internet Explorer v7.00 (7.00.6000.16705)
Boot mode: Normal

Running processes:
F:\WINDOWS\System32\smss.exe
F:\WINDOWS\system32\winlogon.exe
F:\WINDOWS\system32\services.exe
F:\WINDOWS\system32\lsass.exe
F:\WINDOWS\system32\svchost.exe
F:\WINDOWS\System32\svchost.exe
F:\WINDOWS\system32\spoolsv.exe
F:\WINDOWS\System32\svchost.exe
F:\WINDOWS\system32\svchost.exe
F:\WINDOWS\system32\ctfmon.exe
F:\WINDOWS\System32\svchost.exe
F:\WINDOWS\explorer.exe
F:\Program Files\Mozilla Firefox\firefox.exe
F:\Documents and Settings\anguyen\My Documents\Downloads\HiJackThis.exe

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
R1 - HKCU\Software\Microsoft\Internet Connection Wizard,ShellNext = http://go.microsoft.com/fwlink/?LinkId=74005
O2 - BHO: SITEguard BHO - {1827766B-9F49-4854-8034-F6EE26FCB1EC} - F:\Program Files\STOPzilla!\SZSG.dll
O2 - BHO: Java(tm) Plug-In SSV Helper - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - F:\Program Files\Java\jre6\bin\ssv.dll
O2 - BHO: Java(tm) Plug-In 2 SSV Helper - {DBC80044-A445-435b-BC74-9C25C1C588A9} - F:\Program Files\Java\jre6\bin\jp2ssv.dll
O2 - BHO: JurToolbar - {DEE7B1F7-A014-477C-B0C5-23A51AA81DB5} - F:\WINDOWS\system32\jofcsd.dll
O2 - BHO: STOPzilla Browser Helper Object - {E3215F20-3212-11D6-9F8B-00D0B743919D} - F:\Program Files\STOPzilla!\SZIEBHO.dll
O2 - BHO: JQSIEStartDetectorImpl - {E7E6F031-17CE-4C07-BC86-EABFE594F69C} - F:\Program Files\Java\jre6\lib\deploy\jqs\ie\jqs_plugin.dll
O3 - Toolbar: STOPzilla - {98828DED-A591-462F-83BA-D2F62A68B8B8} - F:\Program Files\STOPzilla!\SZSG.dll
O4 - HKLM\..\Run: [NvCplDaemon] RUNDLL32.EXE F:\WINDOWS\system32\NvCpl.dll,NvStartup
O4 - HKCU\..\Run: [ctfmon.exe] F:\WINDOWS\system32\ctfmon.exe
O4 - HKUS\S-1-5-18\..\Run: [DWQueuedReporting] "F:\PROGRA~1\COMMON~1\MICROS~1\DW\dwtrig20.exe" -t (User 'SYSTEM')
O4 - HKUS\.DEFAULT\..\Run: [DWQueuedReporting] "F:\PROGRA~1\COMMON~1\MICROS~1\DW\dwtrig20.exe" -t (User 'Default user')
O9 - Extra button: Send to OneNote - {2670000A-7350-4f3c-8081-5663EE0C6C49} - F:\PROGRA~1\MICROS~2\Office12\ONBttnIE.dll
O9 - Extra 'Tools' menuitem: S&end to OneNote - {2670000A-7350-4f3c-8081-5663EE0C6C49} - F:\PROGRA~1\MICROS~2\Office12\ONBttnIE.dll
O9 - Extra button: Research - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - F:\PROGRA~1\MICROS~2\Office12\REFIEBAR.DLL
O9 - Extra button: Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - F:\Program Files\Messenger\msmsgs.exe
O9 - Extra 'Tools' menuitem: Windows Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - F:\Program Files\Messenger\msmsgs.exe
O10 - Unknown file in Winsock LSP: f:\program files\common files\is3\anti-spyware\is3lsp.dll
O10 - Unknown file in Winsock LSP: f:\program files\common files\is3\anti-spyware\is3lsp.dll
O10 - Unknown file in Winsock LSP: f:\program files\common files\is3\anti-spyware\is3lsp.dll
O10 - Unknown file in Winsock LSP: f:\program files\common files\is3\anti-spyware\is3lsp.dll
O10 - Unknown file in Winsock LSP: f:\program files\common files\is3\anti-spyware\is3lsp.dll
O10 - Unknown file in Winsock LSP: f:\program files\common files\is3\anti-spyware\is3lsp.dll
O16 - DPF: {485D813E-EE26-4DF8-9FAF-DEDF2885306E} (NSHelp Class) - http://leitzkeserver/ConnectComputer/nshelp.dll
O16 - DPF: {6414512B-B978-451D-A0D8-FCFDF33E833C} (WUWebControl Class) - http://www.update.microsoft.com/wind...?1212003677484
O16 - DPF: {74DBCB52-F298-4110-951D-AD2FF67BC8AB} (NVIDIA Smart Scan) - http://www.nvidia.com/content/Driver...aSmartScan.cab
O16 - DPF: {E06E2E99-0AA1-11D4-ABA6-0060082AA75C} (GpcContainer Class) - https://mwmus.webex.com/client/v_myw...ex/ieatgpc.cab
O17 - HKLM\System\CCS\Services\Tcpip\Parameters: Domain = la.local
O17 - HKLM\Software\..\Telephony: DomainName = la.local
O17 - HKLM\System\CCS\Services\Tcpip\..\{EECFA410-8229-46BC-AC52-8977380AEB28}: NameServer = 192.168.1.1
O17 - HKLM\System\CS1\Services\Tcpip\Parameters: Domain = la.local
O17 - HKLM\System\CS3\Services\Tcpip\Parameters: Domain = la.local
O18 - Protocol: grooveLocalGWS - {88FED34C-F0CA-4636-A375-3CB6248B04CD} - F:\PROGRA~1\MICROS~2\Office12\GR99D3~1.DLL
O20 - AppInit_DLLs: rbzziv.dll
O23 - Service: Autodesk Licensing Service - Autodesk - F:\Program Files\Common Files\Autodesk Shared\Service\AdskScSrv.exe
O23 - Service: Autodesk Network Licensing Service - Autodesk, Inc. - F:\Program Files\Common Files\Autodesk Shared\Service\AdskNetSrv.exe
O23 - Service: Flexlm Service 1 - Unknown owner - F:\Program Files\Autodesk Network License Manager\lmgrd.exe (file missing)
O23 - Service: Java Quick Starter (JavaQuickStarterService) - Sun Microsystems, Inc. - F:\Program Files\Java\jre6\bin\jqs.exe
O23 - Service: NVIDIA Display Driver Service (NVSvc) - NVIDIA Corporation - F:\WINDOWS\system32\nvsvc32.exe
O23 - Service: STOPzilla Service (szserver) - iS3, Inc. - F:\Program Files\Common Files\iS3\Anti-Spyware\SZServer.exe

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End of file - 5539 bytes


Thank You so much for your time.