DFI LanParty Ultra-D is goood. Trust me. It's GOOOOOOOoooood.
Ok, here's the thing. There are a lot of people in this world that will tell you it sucks, but it really does not. IT takes some tweaking. My first system I built, I booted up fine. No problems. This board? It took me at least 10 - 20 presses on the power button before it boot up and I got a regular screen.
You have to work with it. It will work though. Looking at your parts, you have all compatible stuff. I think the Ultra-D wasn't as bad of a pain to me as it was to some other people. It's a rock solid board, and you're going to LOVE IT.
I vote against the 3700+ SD. Try for the Opteron 165. Monarch has some deals.
As for the RAM? Doesn't Monarch have the 2x1gb PC-4000 OCZ Platinum sticks for $165? OR look for a deal on those. Those are hte best sticks of RAM ever. It's basically the sticks you have in there, except they're rated for DDR500 3-3-2-8 =)
I recommend a better power supply. Seasonic!