The 6600GT would look good yes.
Remember. The card, as long as it can get to the highest settings in games, will look great at what ever resoloution you run it at really. So when looking for a card, your looking for one that will perform very well, usually at about 1024x768 for average users, and still be getting 30+ FPS.
I must admit though that in the latest games, the 6600GT is starting to have to be ran at Medium settings, though on many games, this is not the case, and on standard resoloutions like the above 1024x768.
I'd try and get hold of a 6800GT or Ultra if you can. Those'd last you a long time.
But the 6600GT is a rather cheap card, and this will do you very well for a long time also, and on standard res's, you should be able to run at high settings for a year I'd say, and still get 30+ fps.