Lessee - being mildly serious, chemistry is the most useful of the three major sciences - it's the link between physics and biology, so you should do that. I see no reason not to take physics as well (not that I did beyond GCSE). I understand the AP courses to be slightly more rigorous than the non-AP, so you should do them.

Basically, do as much as you can, as hard as you can - you'll only regret not learning as much as you could now, when you're too old and don't have the time to study.