Hmm... Stick wid the 5200. Its the best value for money. As i said, go for gainward, it will be around 400-500 RS costlier than XFX but it is worth it cuz its more overcloackable. And yes AMD is the best processor for gaming!
My config:
AMD Athlon64 2800+ (754 pin)
512 MB DDR400 Kingston RAM
MSI K8NM M/B
32 MB ATI Rage Pro gfx card

Maxtor Dimond Max Plus 9 SATA 120 GB HDD

1 GBps Lan Card
Sony Combo 52-32-52-16