Champagne Darjeeling
My best friend sprained her leg doing the Insanity Workout.
I really enjoyed the Insanity workouts, but I never made it to the more difficult level of workouts because I also hurt myself. You have to be really careful to pay attention to form and your body's signals when you're doing high intensity workouts like that.
I haven't used any of them yet, but I know there are quite a few workouts available on youtube. One channel is called Fitness Burner.
I've also used Slim in 6, but haven't done it consistently enough to say if it really works in six weeks.
You also have to remember that exercise alone isn't enough; you have to eat clean, healthy foods along with some good exercise to get results.