Chances are, if your rig can run your operating system and the browser you used to type this comment, it can run about 99% of the games here (that are marked for your operating system)
There are some 3d games here, that might have some kind of requirements. And maybe some types that have driver requirements. Try to install a demo version, if a game has any, before buying. Also, games that might have problems here, tend to list the requirements.