I would worry about getting 256mb bit video cards.
It doesn't matter, this is the 6600GT he's talking about. That card will play any of todays games at max settings. His only other option to go for 256bit would be to go towards the 6800GT which in this case is a matter of money.
Sizco, it comes with VGA+DVI I believe, when you click on manufacturer details it's giving you the details of the PCI-Express card not the AGP model.
As far as which to buy from, well they are both good really.
I've bought a ton of stuff from both newegg and zipzoomfly and zipzoomfly offers good business.
I never saw that newegg had that card until now though that's why I've always been linking to zipzoomfly, because up until now all I could find was the PCI-E version. I'd say go with newegg though only because they use FedEX and zipzoomfly uses UPS and FedEX generally gets it there a day early