Getting rid of Antivirus xp 2008 is nearly impossible.
But if your back ground is blue or has the little sign where it say (warning!your computer is infected with spyware)and the screen saver is the screen saver of the blue erorr code and when you right click on your desktop is missing the desktop tab and the screensvaer tab.You could something about that.Stert>run>gpedit.msc>click ok>you will be redirected to group policy>on the right click user configeration>Adminisrtative templates>controle panel>display>now click on hide desktop tab>now diable it and close the window>click on it again and enable it>ok now right click on your desktop>properties>desktop>now look at the name of the wallpaper you have>open a new note pad and write down the name of the wallpape>copy that code (the one you just wrote down in notepad)>goto start>search>and past the code and search it in all files and floder >once you have searched itthere will like 7files right click them and delete and go to recyle bin and delete them from there>now go back to group policy anddisable screen saver and then enable it>then restart your computer and change the wallpaper and the screen saver
And if you each step you will have your desktop back to narmal!
Oh and yeah,just ignore all of the minor pop ups done by antivirus xp 2008.Hope this helps!
Have a nice day!:)