I'm in about the same situation, only my GFX card is complete shiat. What I'm planing to do is go up over a gig of RAM and add a better gfx card.
Currently
AMD 2500+
MSI K7N2 Ultra 400
512 Kingston PC3200 (going to a gig of Corsair, prolly value ram, but paying xtra $$$ for low latency is...