I've never watched the biggest loser to be honest! I've just sat and watched through level 1 and I'll be honest, it's not easy but it's doable! I think the hardest thing is that it's every day! I know that I need a major kick up the bum so I'm just going to go for it and do my best!
There's 3 people on the DVD, there's her and she talks you through everything really well, explaining why you're doing what you're doing and the effects that it has. Then on the left there's a person doing more challenging versions of things, on the right there's another woman and she's doing slightly easier versions of things. So, for example, when they do pushups, the woman on the left does full on push ups, the woman on the right does easy push ups where you do it from the knees up. I can do push ups but just not many! Most they did was maybe 10. Then there's a mix of weights, star jumps, skipping type actions etc.
So my own person extremely unfit opinion is that it won't be a walk in the park, it will be challenging, but it'll also be doable!
I've even made myself a little diary to keep as I do it, cos I'm sad like that! So I've got a little table for my starting weight and measurements, then each day I'll write a few notes about how I found it that day and then at the end, there's another table for me to put my start and end weight and measurements to compare them. I know some people will think what's the point, but for me things like that keep me motivated so I'm going to do it lol