Yeah, I know that feels. Best thing to do is ask questions and do your own research to the best of your ability to avoid asking 'stock questions'. You have an idea of who and where you'd like to perform, that narrows down the field of magic you could use CONSIDERABLY.
As far as the hospital goes, depending on how much you want to perform (I'm shooting for weekly), you might either be working alongside volunteer services coordinator (which would have been my case in Las Vegas due to the frequency of how much I wanted to perform). OR, because a lot of children's hospitals already have entertainment deals lined up, you might be only able to go every few
months. You will more than likely need to take a class that explains policy, procedures, and protocol. You will also more than likely need to give blood work and proof that you have had a chicken pox vaccination. Also, you may need to run all of what you're going to do by the coordinator to make sure you not going to be a 'liability'. Yes, 'Pyro' is great, but if you're shooing fireballs like you're freakin' Mario Brothers; guess whose volunteerism is going to end quickly?
Again, It really depends on the hospital and it all starts with the volunteer services coordinator. In some cases, this could take months to get it sorted out. Honestly, that's more time to get some practice in.
As far as what to use. Theres a lot out there. Some obvious 'no-God', but that's what's fun in magic; there's so much that, if you look and think about it hard enough, you can create a great routine with it. I honestly don't buy anything unless I can think of a routine I can use with it--or see myself using it within a set.
I agree with not wanting to do 'Uncle's Magic'. There's a few tricks and routines I'm avoiding like the plague (Magic Coloring Book, for starters). Part of it is because I know they are over used, the other part is that if a child has happened to have seen that before, I'm not to get called out on it. With that in mind, I have a rather obscure set of effects that I'm pretty damn positive haven't been performed in public outside of magic demonstrations.
That's really weird that the nearest children's hospital is an hour away from you, as I'm in the same boat. If you say say the closest hospital for you is the Children's Medical Center of Dallas, I'm going to fall out of my chair.