Almost certainly not, and the place is likely selling pirated copies.
While there may be others, the only legitimate game download service I know of is Steam. At least for the PC. Sony, Microsoft, and Nintendo have their respective networks for their respective consoles.
Of course you could always ask the company that sells some of the games on that site whether or not it's legitimate. The maker of the game will have a list of every channel partner they have for distribution and sale of the game.
If you're looking to get games on a bit of a budget, you might consider looking for a GameStop or other store in your area that deals in used games. Better do it fast, before large game makers bribe members of Congress into rewriting big chunks of copyright law (again) to eliminate the used game market. They're already trying to eliminate the first sale doctrine which makes it legal currently, and it's only a matter of time before it succeeds with pro-business republicans in a lot of powerful positions.
I found this site(http://www.urlscan.net/)that sell online downloadable games,software,etc....they have for instance Medal of Honor for $15.00, that said I've tried to find out through google and research if there a pirate site or what have you,,I need some expert help on this matter,,,could someone either teach me how to find this out or tell me if there a rip off,,,thanks alot ,,,Danny