Just another $.02 to add. It does not take much to get in shape. A healthy lifestyle and diet are key, then add exercise. One without the other is like tires without a car or a car without tires. You need BOTH. My advice would be to avoid going to extremes quickly. A body is not used to extremes and "fad diets" over time will lead to training a body to HOLD FAT because it never knows when that next "extreme fast (trauma)" is coming.
Start changing things one at a time. As you stick to them, change another, then another...see results and use that encouragement to build on what you have done. Start with INTAKE...eating habits. Start cutting out nicotene, excess alcohol, caffeine, sugar, pre-prepared meals / fast food. Replace with WATER, FRUITS, VEGETABLES, good foods! As you see changes from your diet then start walking 1/2 mile a day on lunch or at home, then a mile a day, then get up to 3-5. Any more than that is overkill, your body will not get much more benefit from walking 10 miles than it will from 3-5 a day. Besides it's hard to maintain EXTREMES and you will likely fall back into habits. That's why its best to change those little habits by SUBSTITUTING good ones in their place.
As far as workouts. These extreme "boot camps" and "intensity" style workouts are great...IF YOU ARE TRAINING FOR THE ARMY OR THE OLYMPICS. If you want the body of an olympian than GO FOR IT! Just realize you will have to change your ENTIRE lifestyle to get it. If you want to lose weight and look HWP then just eat right, walk a mile or so a day, and 2-4 times a week do a cardio / weight resistance workout.
http://www.bodyrock.tv has some great body weight workout routines that are only 12 minutes long and WILL make a difference for you IF you are also changing your eating habits...again, nothing extreme just what I said above. I work out maybe 2-3 times a week for 20 minutes...walk a mile every few days...and eat right. I still drink moderately and enjoy my desserts. A well rounded lifestyle.
I have friends that kill themselves on restrictive diets and workout so hard they are dead most of the time, sore and tired. They don't look all that much better than me and I get to enjoy ice cream. So for what they are getting by punishing themselves are gains I would say are not worth the extra effort. Afterall, we're not olympians. We just wanna be healthy.
Good luck and START NOW...AND NOW...AND NOW!