I want to setup a Linux machine at home. I will be using it for gaming.
Heh....listen to what you are saying man. Linux is the most "ungaming-est" os ever devised. There is no hardware acceleration to speak of, so all 3d games will be slow, have graphical errors, or overall perform like crap. Speaking of games.... there aren't any. Unless you count emulators and crappy homebrew games of course.
There used to be a company that was devoted to porting pc games to windows. They went under. Why? Well first off, it took up to 2 years to get a game ported, so by then everyone was sick of the game. After all their efforts they got about 12 games, tops ported. That's not enough to justify a gaming machine. Lastly, even if you manage to get a great game ported to linux quickly... the hardware will fight you every step of the way. There is not really a linux evuiveelent of directX. What hardware acceleration you get is usually integrated into the game. As most game developers aren't the best low-level programmers that generally means you get 0 hardware acceleration.
Long story short, for gaming specifically, linux is the worst possible choice for an os. I never say this, but you'd be better off using dos. At least there is a vast library of dos games to play as opposed to the 40 linux games (39 of which involve penguins and bad rip-offs of classic games you can play in mame anyway).