Might I suggest giving openSUSE a try: http://software.opensuse.org/131/enThing is I've never used any Linux based OS and the thought of installing some version of them all has crossed my mind but I've never converted that thought into action, I might as well give it shot now that you mentioned a version.
What's the learning curve on such an OS?
It's a very user friendly distro and has a great community to help you out with problems, yet it doesn't hold you back when you feel like jumping off into the great wide yonder. Oh and it also has a cute gecko as its mascot.
I suggest downloading the GNOME LiveCD from the page I linked, put that on a USB stick and have a look. Instructions for installing etc can all be found on said page. It'll likely be quite different (or at least feel different) to what you are used to in Windows, but I'm sure you'll get the hang of it in a couple of minutes.
Otherwise I don't think there's anything more to add than what FAST6191 already said.