The wow client that works on Mac OS X comes with a built-in recording function. Has a whole separate added "Mac Options" window where you can control keybinds for recording and compressing and whether to record the UI or not. Long story short you can record while playing normally, but the film comes out with no UI showing whatsoever. Great if you like cinematic film.
Examples in sig. Downside is ofc that now you're playing on a Mac. This was the only reason I made the switch, and something I've regretted a few times but if you're an artist then you're willing to suffer.
http://www.wowpedia.org/Mac
http://www.wowpedia.org/Mac_Video_Recording_and_Editing