I might register at some other time, so i can comment but...
Well done you, it's good that you want to loose weight, to make yourself look and feel better. Although no matter how much you weigh, if you feel good, nothing else matters.
How about instead of trying to lose massive amounts of weight you try to cut the fat and build up muscle. Get some Whey Protein and possibly just get a trainer for a one time thing so they can compile a good routine for you.