Hi lovely,
Well firstly, like a lot of other people have said... don't worry about your size, burlesque is for everyone and so you may as well start now!
Re: weight loss, i would recommend Weight Watcher - i have done it a couple of times, and you can lose weight amazingly fast whilst still eating nice things I didn't go to classes, i just signed up online. And for exercise dancing is great for getting in to shape, and i also find hoola hooping great!
Good luck!
xxx