abirdee~~
I agree with Pilates. Pilates work ALL areas of your stomach, sides, back, everything! It is a much different workout that say crunches or tapes that involve things like that. I love Pilates because you're working on your core, flexibility and strength! Almost makes you forget that you're working your muscles!

But I tell you, after the first couple of times I did Pilates, I was sore in places that I didn't know I had!! I have a Denise Austin Pilates/Yoga tape that I love because it's a good 20 mins and doesn't get my heart rate up too fast so I can do it anytime, sometimes before bed too!
Good luck!