(to Unregister DLLs, goto CMD prompt and type "regsvr32 /u filename.dll" where filename.dll is the dll you want to unregister)

Stop XP Antivirus 2008 Processes:
XPAntivirus.exe
XPAntivirusUpdate.exe
xpa.exe
xpa2008.exe

Find and Delete these XP Antivirus 2008:
xpa.exe
xpa2008.exe
XPAntivirus.exe
XPAntivirusUpdate.exe
shlwapi.dll
wininet.dll
XP antivirus
XPAntivirus.lnk
Uninstall XPAntivirus.lnk
XPAntivirus on the Web.lnk
XPAntivirus.url
XP Antivirus 2008.lnk
Uninstall XP Antivirus 2008.lnk

Remove XP Antivirus 2008 Registry Values:
HKEY_USERS\Software\XP antivirus