I was a little worse off than you when I started. I am 5'11" and tipped the scales at an ugly fatboy weight of 310. I too wanted to get back to the 205 I was when I got married 20 years ago, but I knew that was too much of a goal and I would get frustrated quickly.
I saw some co-workers have success with Weight Watchers so both my wife and I joined (she didnt need to lose much, but her's was more for moral support for me). In addition to this, we also walk a little over a mile and a half every night and do some workout (either ab workout or some upper body on the bowflex).
Fast forward a little over a year - I am down to 255 and she is down 27 pounds herself. Because I dropped the weight I did, she has agreed to let me get certified (She didn't want me to risk anything when I was so overweight - and I will be doing my second day of confined water dives tonight - should finish Sunday). I still have a long way to go - but I have also changed my goal to 225 due to my muscle structure. It is a pain in the arse having to buy new clothes all the time, but it is very nice going from tight 44 pants to loose 40's and on a good day, I can wear 38's.
Good luck with your programs and plans - but remember, it is not a "do it now" type of diet. It is a total change in lifestyle and how you view foods AND portions.