If somehow I could magically be completely happy and content being a girl, yes I would do it. I've always hoped that 'one day' I'd be content as a girl, because I really do not like the feelings of hating my body. I really want to feel 'right' in my skin, so if somehow female felt right, I'd take it!
That said, I'd much rather go back and magically be born a boy, since that's what I know would feel right for me, but either way if both body and mind matched, that would be awesome! I feel like either way I'd still be me, I'd just be a more content me.