Which version of Linux is best for Gaming? I want an operating system that requires less cpu demand than Xp - providing a better overall performance.

Ubuntu is good choice if you want Linux for gaming.The good part is it comes with excellent community that helps you solve the problem,you can ask your problems related to ubuntu at http://ubuntu.wordpress.com or http://ubuntuforums.org

If you want to go with commercial linux then Linspire,Mepis premium is good choice.If you have good internet conection or amazon account better get the Debian DVD's.that will have you setup of drivers & games.If you need any information feel free to PM or post infor here so that others can help you better.