What size/breed of horse should I get?

I am about to start riding again. I haven't had much experience- mostly just here and there riding. Haven't rode since I was 10 and I'm 14 now. Im 5'7 so I'm kinda tall and I weigh between 130-145- it fluctuates. Anyway I was just wondering what breed is most docile/good for beginners? I know an older more experienced horse would probably be best. also what height? I was thinking 16hh or 17hh? Would that be okay?