KavazovAngel: Is Windows Server 2008 R2 good for every day use? Like playing games, producing music and stuff like that?
EDIT: I know we shouldn't talk about this, but is this SLIC loading stuff I see on the net safe to use?
Since it's a server OS some gaming functionality is missing by default and will need to be manually installed (and I'm not just talking about running the DirectX installer), and even then not everything will work, especially certain legacy games. For non-gaming purposes it should be mostly identical to Windows 7, however.
Also note that most or all consumer security software will refuse to install on a server environment because they see the server OS and think you're trying to pull a fast one by using a free/cheap personal AV for corporate use.
2008 R2 is also totally unsupported by all games and almost all programs (if they run it is not intentional), so when you run into problems--and you will--you won't get much help from tech support beyond "buy Windows 7 k thx".
Windows 7 is expensive, but it's clearly preferable to trying to shoehorn gaming usage into a server OS. Everything just works right out of the box with 7, and if it doesn't you can get full tech support from software vendors.