Goto Start > Help & Support and type in Compatibility Wizrd in the search box.
Xp can run many older games, but you may have problems with some.
The Compatibility Help pages gives you two options; Run the wizard or change settings manually.
I hope this helps.
I am trying to run command and conquer red alert for windows 95, but I have windows xp. Is there a patch that I can download to make this possible?