Linux I am sure a wild guess would be Centos or some other Red Hat clone.
I would also add that it no longer takes a Geek to run Linux it is now as easy if not easier than Windows. do you run Firefox, OpenOffice opps guess were they came from yep Linux or the open source community, the hardest thing I find in getting used to Linux is the program names Kaffeine, Vlc, These are media player,s! I would also add Smplayer one of if not the best media player around.
Games ah yes the most important thing, try Ultimate Edition Gamer’s download it for free burn it to a DvD and run it live you don’t even have to install to try it.
I am not against Window’s at all I just have a balky computer that did not like Vista instead of paying around $300 for an operating system I installed and started running Linux daily now I love it.