I can't speak for anyone else, but I found that easing myself into a healthy lifestyle was a lot easier than diving head first into it.
Initially, I started working out 3-4 times a week and didn't change any eating habits. That included multiple trips to taco bell and a pizza or two a week. Once I noticed that much of my workout was being wasted because I was still eating these things, I slowly started to take away bad foods and add good foods. I started drinking high-protein Boost in the mornings and cutting back on the fast foods. I learned to use a Foreman grill
and cooked up chicken breasts and salmon for dinners. I continued working out and slowly learned more about it just by going and talking to people.
Well, before you know it taco bell was no longer a part of my diet, I was in better shape, and going to the gym sorta became embedded into my routine. I think if you make small steps but stay focused on where you want to be, and maybe improve one thing a week, you can gradually ease yourself into a healthy lifestyle. I think the #1 reason why diets and workout regimens fail is because it's too drastic of a change and not sustainable in the long term.
Maybe you should make it a point to post back in this thread every time you improve something, that way you'll have a record of your changes and progress, and maybe gain some moral support from others as well.