http://www.ehow.com/how_4800744_delete-genuine-warning-windows-xp.html
http://blog.taragana.com/index.php/archive/how-to-disable-windows-genuine-advantage-warning/
1. Lauch Windows Task Manager.
2. End wgatray.exe process in Task Manager. <<
to stop it, locate and right click on the wgatray.exe file (under
A. go to properties > security tab > advanced
B. now uncheck "allow inheritable permissions from the parent..." you will be asked to remove or copy, choose Remove > click "Yes" and OK to close the window now you can end the proccess and it should not start up again.
C. Next you will need to give admin permissions to delete the file
right click wgatray.exe > go to properties > security tab > click Add > type administrators and click OK and OK again.
3. Delete WgaTray.exe from c:\Windows\System32.
4. Delete WgaTray.exe from c:\Windows\System32\dllcache.
5. Lauch RegEdit. (open run box and type regedit)
6. Browse to the following location:
7. HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\Notify
9. Delete the folder ‘WgaLogon’ and all its contents
10. Reboot Windows XP.
DONE