The "Program Compatability Wizard" is what you're looking for. Mine is
in Start/Programs/Accessories. But you should go to Start/Help and type in
"Program Compatability Wizard" first, and read up on how to use it.
Good luck with that, but I have never been able to get the Compatibility
part to make an old 98 program or game work effectively.
You may want to consider using a Virtual PC to give you this functionality
if you have no joy with the compatibility way.
See the thread from Trixie dated 21/11/08 03:49 for possible further
pointers.