Not with an Intel Board - but you'd have to go with a better Celeron. You couldn't put a P4, or I think a P3 in a Celeron Socket - wouldn't work. Then you'll have to get a new Motherboard - which leaves it open for anything in your budget.
I recommend not getting an AMD unless you're prepared to get a 64-bitter; Intels are so much more powerful. For games? Who knows; but if you're going to get an AMD get an Athlon - not an old K-6
A Knight is sworn to Honour. His heart knows only Virtue. His blade defends the helpless. His might upholds the Weak. His word speaks only truth. His wrath undoes the Wicked.