$400 to buy a new MB, Proc, and Memory!
 

This is what I'm looking at:

MSI nForce3 250 Chipset Motherboard "K8N Neo Platinum"

AMD Athlon 64 3000+, 512KB L2 Cache 64-bit Processor

Mushkin Dual Pack 184-Pin 1GB(512MBx2) DDR PC-3200


Any problems with this or something I should look for over this?

All great name brands, all good reputations.

Looks really good.

It isn't bad but I'd seriously consider using existing memory in a newer board. Upgrade RAM when you have funds available. The 754 socket has seen its day. The 939 socket and nForce 4 are here now.

Other 939's are cheaper but you might squeak in an Asus A8N-SLI Deluxe combo with careful shopping. Here's one with a 3500 for $490:
http://www.zipzoomfly.com/jsp/Produc...-240418&ps=ho2

You can shave off about $50 by going with a 3000.

I'm trying to keep it under $400 bucks, although I may switch out the MSI MB for a DFI Lanparty board, they're getting great reviews.

My previous MSI board was a bit finiky, but I've built a few others with MSIs and had no trouble. Right now I'm running a rock-solid Gigbyte, so that'd be my suggestion. Other than that, your picks look just fine.