Scott, may I suggest you upgrade your PSU to a minimum of 450 watts. Then get a graphics card with a fan on it, I don't trust passive cooling. And seeing you only have 3 PCI slots you don't have room for a PCI slot fan to take out the heat from the 6200 128mb card you're looking at.
A better palce to find a card is PriceWatch.com. Many great bargains there. I'm using a GF5600Ultra 256mb card that runs SHIII just fine. Here's one that's as good of a bit better and has free shipping....
http://www.pricewatch.com/video_cards/5884-1.htm
Edit: The 6200 is better than the 5500. But the 5700 256mb card is about the same or even a bit better than the 6200, which has only 128mb of RAM but does not have a cooling fan. And you do want a fan for cooling seeing you're running the Dell which has no cooling fans other than the PSU.
Next computer you get, it would be better for you upgrade wise, if you build your own. You'll have a much better pc than you can buy, and for less money than for one that's comparable from any of the companies.... Dell, HP, Compaq or whatever.