Any windows OS will do you well. Hell probably even Windows 2000. Just remember that if you want to install something like Windows 7 and you are using the same key that another PC has make sure both PCs have the same external IP, otherwise your windows key might get revoked or somethig (it's happened to me, I just called them and I got it back though).
Linux will be more viable to YOU if you have an older/underpowered PC or unless you just favorite it (considering it would be a new OS to learn how to use, it's fairly simple though). What are you PC specs, RAM and processor?