Linux are used by alot of IT professionals. Linux has a lot of powerful features that windows doesn't, straight from the terminal (bash screen). And with built in applications like awk, grep, and other commands, you can do quite powerful stuff text based. Linux is quick because of the fact that it doesn't have a huge interface driving it like windows does, and it is designed to be more IT friendly, and not so user friendly. Where as windows is "suppose to be" user friendly over IT friendly.
It's a powerful tool, and there are heaps of unix tutorials online. If you want something that has a strong GUI and is linux, try Ubuntu. It's quite popular around university, and is relatively quick.