RE: Fixed wing > rc heli > full size heli
I learned a while back with RealFlight and now I have Pheonix, I really don't find much of a difference in reality. Use the SIM to get some of the basic skills down or try new moves and then head on out to the field.
As far as beginner Heli's go, check out the Blade 130X BNFs. It is flybarless and flies very similar to the larger more expensive helis believe it or not. It is smaller than the 450 size but is one of the few to have a torque tube tail. Most guys at my field that fly the bigger ones also have a 130X for practice. They are fairly inexpensive to recover from a crash, although you'll quickly learn to add a few aluminum parts where needed.
The best piece of advice I can give is start out with the trainer pingpong ball + sticks on the landing gear to help with tip overs when learning to hover and land then dump them and learn to hover above ground effect (higher than 3-4'). Hovering under 4' for a beginner while comfortable and be extremely frustrating to control because you're fighting the rotor wash against the ground which will push it all over the place. At altitude heli's will hover fairly well, just don't hover to close to your head!
My collection: Blade 130X, Trex 250, Trex 450, Gaui X5
Good luck!
Greg