Curves is AWESOME! I used to go and LOVED to go! I injured my knee over the summer and haven't been able to do any exercise -

But - I was over 300 pounds and never once felt out of place at Curves. They are very nice and never make anyone feel bad there - there are old women, young women and in between women of ALL weights there.
I didn't lose any weight on it, but lost around 10 inches overall - I wasn't watching what I ate, but if I had, I would have lost weight too.
NOW I'm losing weight on LAWL, but can't exercise - one of these days I'll be able to do both!
Give it a whirl! You will LOVE it!