A few years ago I toyed with fedora and at the time would have suggested it. Currently I'm using ubuntu and think it is a little more user friendly. Some think ubuntu has a little to much bloat but compared to windows you'll probably think it is stream lined :p You do not really need to know linux to use either. Ubuntu, and probably fedora, has managers that will still programs for you but you can still do it manually when you want.
http://www.ubuntu.com/http://fedoraproject.org/en/get-fedoraI'm duel booting win7 and ubuntu. I let grub do my boot up instead of windows but that is simply preference. If you want to run linux from usb look at unetbootin. It is slower but being able to carry it with you has its advantages.
http://unetbootin.sourceforge.net/