I'm just coming back after several years and and a baby, but I was successful with the SparkPeople program several years ago. I found that the exercise and diet worked together. I started to see cookies as extra time on the elliptical and they we're so appealing anymore! I started by just tracking, then modifying what I ate to stay in my calorie range, then modifying that to stay in my nutrient ranges (for me that meant working to eat enough protein).
I know that with SparkPeople, it's really up to me. If I hit all of my benchmarks, I will lose weight even if it is frustratingly slow sometimes. Patience and persistence worked.
Good luck in your journey. I'm sure you'll do great!