You did not get to 252 pounds overnight - it took a long time. To take of weight permanently, you need to do it slowly with, as already suggested, life style changes.
Done quickly, even by surgery (and again as already suggested), it often is a temporary fix.
Eat sensibly and start moving. Your largest muscles are in your legs - you burn the most calories using them, plus lots of other good things, like helping to pump blood. Riding a bicycle outdoors is excellent because it's "low impact" and doesn't beat your knees or hips. Unfortunately, it's too cold up north to do year round.
Long term, the gym is almost never successful because it's bbbbbbbbbbbbooooooooooorrrrrrrrrrrrriiiiiiiiiiiiiiiiinnnnnnnnnnnnnnnnggggggggggggggggg! Instead, find a good ZUMBA class, because it's FUN - therefore you're far more likely to stick with it. I've been doing it for almost 8 years, sometimes twice a day (remember, I'm retired). If doing exercise with a bunch of women shaking their rear ends doesn't get your heart rate up, you've got worse problems than excess weight!