I would try and get a new PC if I was you. Even if you do get a new Graphics card your CPU is so old. And if you do get a Graphics Card will you be able to install it. Because I would not pay to get it put in. even if you get a 9600GT with a new comp would be better imo.
i was originally thinking the GT220 and the GT240, but i read they're pieces of shit from somewhere, anyway im thinking the 5770 now, and i'll probs put an order in for it soon, thanks for the help guys