computer freezes while playing solitare

I have a computer running Windows 98 thast I purchased from a friend of mine. I recently re-formatted the hard drive and re-installed everything back onto it and have been having trouble with my computer freezing up whenever I am playing Freecell orSolitare card games on it. The computer seems to work fine for pretty much anything else I use it for (surfing, e-mail, word proccessing etc…). Any ideas?? It is pretty much driving me nuts.

Thx

DH