The biggest problem is eating a lot of white flour and refined sugars. You should look into eating more of a mediterranean diet. Eating is only half the problem. Excercise is critical. It is best not to go overboard at first because you will just burn yourself out.
Find something you enjoy doing and focus on that. I enjoy riding bikes so I signed myself up for a tough event later in the year and used that as my motivation. I have now been doing that ride for the last 5 years and loving it. I have lost 50 pounds and have kept it off.
I also have an XBox with Kinect and only buy games that require me to get up and moving. I don't buy regular games for it. I also have the Nike+ Kinect Training game and I find that one works best for me.