Yes, Geminosity, Gentoo is a good distro but it's geared toward experienced users because of its manual command line installer and the fact that you have to compile everything from scratch. The end result though is a highly customized and tweaked system built from the ground up just for your PC. If you like Linux, like I did, by all means migrate to Gentoo.
Also, like many others have mentioned, I recommend Mandrake as a beginner's distro (just remember to back up first!) but it's only good use really is trying things out because of RPM dependency hell, bad security, difficulty in configuring (editing the auto generated config files or recompiling the kernel often breaks everything), and all of the bloat that gets installed (even if you go to the manual package selection and uncheck everything you still have things on there that you'll never use).
Finally, you can run Steam in Linux using WineX but it's a fight from the start as various problems occur such as low FPS, bad sound, Steam glitches, etc. I managed to get NS running (and quite playable too) but not at Windows speed.
Good luck!