I read through this, thinking you were older than sixteen. Once someone mentioned your age--oh, man, I'm really sorry about this. Teenagers shouldn't be exposed to this sort of problem.
Anyway, back on topic: What you really need to do is to sit down with your family and your doctor and take a nice, long look at both procedures: risks for mortality, risks for infection, risks for complications, what (proposed) benefits you're looking at for each procedure, what kind of maintenance you'll need to undertake in order to get the most out of either operation (medications, check-ups, anything). Talk it over, and give this decision some serious thought, and then only proceed once you're ready and completely sure of yourself. Don't be afraid about making the "wrong" decision, just do what feels the most comfortable to you.
This is where I'd suggest my personal option, but really, since I'm not in your position, I really can't say what procedure I'd go with. If you want a better shot at a relatively healthy (and relatively guaranteed) life, you're probably better going with the transplant; if you're willing to try and fix the problem once and for all, go for the experimental surgery. Do whatever you think would let you live a better life.
If you want a more objective opinion (lol, like those exist), go for the surgery. If it's botched and you're still alive, you'll still have the chance to go for a transplant. If it works, you'll have helped advance the medical field and potentially help hundreds, if not thousands, of other people suffering from this condition as well and reduce the need for donor hearts. If it doesn't work, the same thing applies; it's a win-win for medicine (unfortunately, though, not necessarily for you).
Of course, I'm not a doctor, so this post probably amounts to nothing more than a mere rambling and a regurgitation of everything else you've read in this thread. Just do what you think is right, and hold fast to that conviction. Don't let others force you into doing something that you're not comfortable doing, especially when your life is at stake.
Good luck, and pray for the best.