I highly recommend looking into www. slimbodycoach.com. They are a wonderful company that has a free website where you get daily motivation from others in the same situation as you. There's a lady that has lost over 100 pounds and she's bound to a wheelchair, so she has proven that exercise isn't even necessary. They have wonderful safe weight loss products you can purchase through them. Their protein shakes are the best and don't have HFCS (high fructose corn syrup) in them. Stay away from anything sugar-free too -- they are worse for your health than the real thing. You can enter there contest which is what motivated me -- I was the Round 1 winner in 2007, so it's the real deal and it really works. You have to change your metabolism.
It teaches you to change your lifestyle by eating real food. You eat healthy choices 5 times a day, 3 hours apart, with each meal containing a 1/2 cup of each: protein, carb, and color carb (veges & fruits). The calories you eat depend on your weight x8 (so it lessens as you lose weight). It's time consuming at first to figure out the calories and protein grams of the things you like to eat, but after you get it down it's worth it. It takes time to change habits, so allow yourself that time.
You should drink 10 - 12 oz. glasses of water each day (I drink before and after each meal to help me get it all in with a routine). I found that it helps lose faster if you eat at least 100 grams of protein per day. You are allowed one cheat meal a week (anything you want and only lasting one hour). This helps my brain and willpower by saying "I can have it later".
I also would highly recommend water aerobics at first until you lose some of your weight and get more in shape. Then you can slowly start walking -- like 5 mintues every day for the first week, and add 5 minutes every week. I might even consider doing that in the evening, and water aerobics in the morning. I personally love aerobics, and really love the Turbo Jam series right now.
I was really happy that I found this company because I don't feel like it's a diet. It's just learning how to eat right and changing your habits and lifestyle. I always like to try things the natural way first before I would ever consider surgery or other options. On the site, they will answer any questions you have as you go. I found it helpful to plan out what you will eat tomorrow the night before -- less room for cheating. I wish you the best!! ~D.