I bought an old Biggest Loser Workout DVD (Bootcamp) and I am really enjoying it! The burn factor is high but not so bad that you can't do the exercises and there are ways to up the intensity if it gets too easy. So far, I am only doing Level 1 and will add Level 2 in two weeks.
If you are the type that likes to work out at home (or you don't have time to go to the gym) this is an excellent DVD!
I also bought the Jillian Michaels one, I don't know why, I have never really enjoyed her. I found this one a little hard to keep up with and it doesn't even use weights! This one will stay on my shelf until I am stronger.