If I could get the body of a dragon, I absolutely would. I would then fly around, occasionally breathing fire in delight, just enjoying the feeling of flying and of being a dragon.
I would settle for the body of an animal that has been proven to exist instead. What I would do would depend on which animal I ended up with, I can't decide on one right now.
If I'd have to be human? I think I'd stick with my current body. At least I'm familiar with this one.
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Yet in my new wildness and freedom I almost welcome the bitterness of alienage. For although nepenthe has calmed me, I know always that I am an outsider; a stranger in this century and among those who are still men.
-H. P. Lovecraft, "The Outsider"