I like Linux, Ubuntu is nice, and you can get he CD's for free. It can take a bit of getting used to, but it is reasonably straight forward. Don't expect a Windows experience though. Main issue I had was getting nVidia drivers installed, it isn't a case of download, double click, reboot, sorted, and it drove me nuts till I fathomed how to do it.
You can/will/might find issues like that, however, if you are after something to do, it certainly fills that.
You could always download Virtualbox and run it in that first.
Try Ubuntu or have a play with
http://www.pcbsd.org/ it's free so nothing to loose.