Well if your friend is a gamer, he should be looking a step or two above those particular cards. The 9600 series being the "mid range" offerings from a few generations back, and the 6200 being the "mainstream" or "low end" offering, though FAR superior to past mainstream offerings (like the 9200, 5200, or mx440).With modern games in mind, you really dont want to skimp on your choices, especially since prices are very competitive for the entry level performence cards, like the 6600, 6600GT, or 9800pro, all sitting around $100-$160. the 9600xt should be a little bit faster than the 6200, but its not gunna be worth the money to be honest. The 6200 will actaully be on par, (or slightly faster/slower depending on game/benchmark) with the 9600 pro, which as you can guess is really not a whole lot slower than the 9600xt. A quick look through newegg and I see the 9600xts sellin for $90-$110 or so, and at that price you should just pick up a 6600 standard, like
this one for $115. And a 6600 will blow both those 2 cards away (6200 and 9600xt), and its about on par with the 9800 series. Your step up option being the full blown 9800 pro
like this for $125 shipped.
If hes gamer, hes gunna want something more powerful. If hes just lookin to blow a little bit of money, and looking to get a bit of a boost in gaming power, either is a good choice, personally Id go with the 6200, it being newer technology, and the card itself having a lot of modding potential. But really you'd have to post up his specs, budget, and any list of games hes hopin to get better fps in, then we could really tell ya whats the best performer, or best value...