Ad Aware gets rid of it....

Unexplained computer behavior may be caused by deceptive software
http://support.microsoft.com/kb/827315

Run a /thorough/ check for hijackware, including posting your hijackthis log
to an appropriate forum.

Checking for/Help with Hijackware
http://aumha.org/a/parasite.htm
  http://aumha.org/a/quickfix.htm
  http://aumha.net/viewtopic.php?t=5878
http://wiki.castlecops.com/Malware_Removal_and_Prevention:_Introduction
http://mvps.org/winhelp2002/unwanted.htm
http://inetexplorer.mvps.org/data/prevention.htm
  http://inetexplorer.mvps.org/tshoot.html
http://www.mvps.org/sramesh2k/Malware_Defence.htm
http://defendingyourmachine2.blogspot.com/
http://www.elephantboycomputers.com/page2.html#Removing_Malware

When all else fails, HijackThis v2.0.2
(http://aumha.org/downloads/hijackthis.exe) is the preferred tool to use (in
conjuction with some other utilities).  HijackThis will NOT fix anything on
its own, but it will help you to both identify and remove any
hijackware/spyware with assistance from an expert.  **Post your log to
http://aumha.net/viewforum.php?f=30,
http://forums.spybot.info/forumdisplay.php?f=22,
http://castlecops.com/forum67.html, or other appropriate forums for review
by an expert in such matters, not here.**

If the procedures look too complex - and there is no shame in admitting this
isn't your cup of tea - take the machine to a local, reputable and
independent (i.e., not BigBoxStoreUSA or Geek Squad) computer repair shop.

I got this Antivirus XP 2008 last night. I spent two hours trying to get rid
of it then, Itried to delete it from the add/remove programs list and just
got an error box saying that the uninstaller had experienced an error and had
to close. I tried to do a system restore and was unable to do that. Then I
tried this website and read h ow others were handling it. I downloaded SPybot
and Malwarebytes, both were free downloads. I ran them simutaneously and then
rebooted my computer. It took me about six hours this morning to complete the
process,  but since then I have seen no sign of Antivirus XP 2008. I even
checked again in the add/remove programs list and it is no longer listed
there.

Manual XP Antivirus 2008 Removal Instructions:

Unregister XP Antivirus 2008 DLL Files:
(Learn how to do this)
shlwapi.dll
wininet.dll

Stop XP Antivirus 2008 Processes:
(Learn how to do this)
XPAntivirus.exe
XPAntivirusUpdate.exe
xpa.exe
xpa2008.exe

Find and Delete these XP Antivirus 2008:
(Learn how to do this)
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:
(Learn how to do this)
HKEY_USERS\Software\XP antivirus