Curves?
I used to work out at Curves (a six month stretch about 3 years ago before my neck injury) and I LOVED it. I'm planning to start up again there very soon, since I'm almost 6 weeks out now and need something more than just walking. The great thing about Curves is that everything is laid out for you - it requires very little instruction. However, there are always instructors there to help you correct your form if you're using a machine improperly. And the machines are designed to work you as hard as you work them. You can always go by and take a tour, and sometimes the locations will set you up with a free week trial. Give it a try - I think you'll like it.