If your antivirus software requires admin rights to update itself, I
wouldn't use it - and either set WU to do autoupdates in the middle of the
night, or install WSUS on your network...
Bottom line is, you really can't stop anyone with admin rights from doing
anything.
Are you using Active Directory?
"Lanwench [MVP - Exchange]"
In
XP Home or Pro?
Basics would involve making sure the user was a limited user only -
beyond that, more info is needed.