If you want a very nice simulator for a demo there's one called RC Plane Master. Very good realism, but you only get one plane and one field to fly on it, but hey, it's free. Then if you feel comfortable, I would say go with one of GWS's beginner models; the Tiger Moth, Slow Stick, or possibly the E-starter. I haven't flown any of these, but from what I've heard on this site, people have had great success with all 3. I wish I would have done this instead of getting a Ready-To-Fly like the Aerobird. Because now i'm ready to move up to 4 channels, and being only 15, don't want to spend the money on another transmitter, receiver and the works. Anyways, I hope this helps you a little bit and good luck.
-John
I forgot the website for the sim. Here it is. Just click Download Demo. It's 7mb.
www.realitycraft.com/index.htm