What games can i play on nvidia geforce gtx 460 768 mb ???

Most of the latest less graphic intense games should sun fine (ex. call of duty) and pretty much any older game of it's era.

you can run any new games at mid-high settings.

Can you tell me some of those games,please?

S.T.A.L.K.E.R. - all three parts
Crysis - All three parts
Colin Mcrae Dirt - All of 'em
Sniper Elite V2
Fallout 3 and New Vegas
Mafia II
The Elder Scrolls V - Skyrim
Need For Speed - pretty much all of them, including the run, although i heard there is a new one coming out, called "most wanted" (yeah, I know, the guys working on it must be really creative).

Well, you get my point, like iamcacao allready stated, you'll be able to play pretty much anything.

You can check what you can and can't run at this site:
http://www.game-debate.com/

The GTX 460 768 MB has a score of 8. The simply search for that game and look at it's minimum requirements, if the number in the "GPU" section is below 8, then the card will be able to run it, although 8 is usually even more than what is recommended. But seriously man, the card will run 99% of today's games just fine.