If you are looking for a workout system to use at home, I highly recommend The FIRM workout videos. I started using them about 2 years ago and they helped me lose 20lbs. Since we are going to Hawaii again in June and I pretty much stopped working out since before the holidays, I decided it was time to break out the old Fanny Lifter, and let me tell you, they don't call it the Fanny Lifter for nothing ;)
I strongly believe in weight training in combination with aerobics for women. We need to build that muscle in order for our bodies to burn more calories when we are doing nothing!
I've also gotten Turbo Jam and it is more fun to do, but I haven't done the entire series yet so I don't have a review.
One word of warning about the FIRM though, starting out totally sucks. I didn't make it through the videos the first couple of times I tried and my legs still KILL me after I do a big workout if I've taken a long break.