I'd want to be strong and indestructible. Like, not necessarily fully immortal, but taking zero fall damage and stuff, you know? Twilight-esque vampire sort of power - stop moving cars with your hands, jump very high.
There are loads of more practical powers out there in the worlds of our imagination, and this one is not exactly the most useful for an introverted homebody, but heck, the best dreams I ever had that haunt me decades later are the ones where I distinctly knew I didn't have to be afraid of anything and there was power in my hands. Especially the feeling of jumping from up high and flying down hard while fully knowing I will not be hurt. Gah.