I'd get:
MSI K8N Neo4-F Motherboard
AMD 3200 Socket 939
1Gig G.Skill (Single stick) RAM
Yes, dual channel is better, but if you have your own ram already or going to get some in the future, you can dual channel with another single gig of ram. http://www.newegg.com/Product/Product.asp?Item=N82E16820231036
= about 310, a little over your budget but definately worth it.
oo my fault, I didn't see that.
Yeah I'd say go with the asrock mobo in your case, I don't know much about the brand but the agp/pci-e compatability is very helpful.