Overhauling my ancient desktop. Could use some help.

I need to upgrade my venerable Socket A/DDR1/AGP system to something better capable of running today's games. However, since I've been out of the loop for so long, I am hoping that I can tap the knowledge base here for some assistance.

[Here's my current rig; just for the LOL's.]
GA-7VT600-L
Athon XP 2600+
Radeon 9600PRO
512mb PC2300 OCZ
[350w, XPSP2]

I'm looking to replace the above, except the OS and, if at all possible, the power supply, with a Socket AM2/DDR2/PCIe setup. I don't have much to spend so bleeding edge parts are out of the question. There is a great GPU guide here so I probably wont need help with that. What I really need are suggestions on what motherboard, CPU and memory to look at. Also, let me just state that I don't intend to overclock and that quality is important to me; I need these parts to last. So, with that in mind, what would you recommend for a 200-400 budget?

(Note: If I can afford it, I'd like my setup to be able to run NWN2 at 1280x1024 with HQ textures and most of the options, such as grass, enabled. It's not that I think NWN2 is anything amazing, just that NWN2 is the game that put the final nail in my rig's coffin.)

Thanks,
Kyoujin