1. Why do you want to reformat Windows?
2. Since you have legally purchased a license with your computer, I would have no problem downloading it after finding out where it is from this little Swedish website.
3. Since I use Linux, I have to say that this is one problem that I don't have anymore. If you are learning computers, you could just learn something that works the way you want it to.
http://www.linuxmint.com/mirrors.php?id=15 Download it, burn the file onto a CD, restart the computer with it in and you can try it out. If you don't like it, take the CD out and nothing will have changed. If you do something, good or bad, it won't be saved when running off the CD. You will have to go through a setup phase to install it to the hard drive before it is easy to save files and settings.