Go with the Radeon 9800 Pro. It'll kill a 9600 XT no matter the memory. Remember one thing however: there are two version of the Radeon 9800 Pro 128 MB. The one you found for $150 is probably the 128-bit memory bandwidth version. Forget that shitcan...you want the 256-bit, 128 MB Radeon 9800 Pro. It's $200 US.
Another choice would be the Radeon X700 XT or Radeon X700 Pro or GeForce 6600 GT...but those aren't out in AGP yet, only PCI-E. They *will* be about in AGP soon though, so it might be wise to wait. They're also $200 US. If ya want a videocard ASAP, you can't go wrong with the Radeon 9800 Pro. Just about any manufacturer will work! If ya want a videocard for $150, then that's a completely different story. I'd check out the Videocard Buyer's Guide published by the one and only if ya need more information:
http://www.tfproject.org/tfp/showthread.php?t=68344
PS: Everything else looks good, but I'd get the 1 MB L2 cache version of the Athlon 64 3200+. It's worth the extra money! Oh, and if you use Pricewatch, make sure to check out the company on
www.resellerratings.com. That, or just shop at NewEgg.
-Lasereth