When it comes to weight loss, the majority of your progress will come from diet, not exercise. So I would focus on what changes you can make to your eating plan if you feel like you're not doing well with making healthy choices.
As far as exercise, what matters most is that you're doing something you enjoy that challenges you. I'd aim for 30 minutes (or so) of cardio exercise, 3-5 days per week, as well as strength training twice a week. There are videos and workouts on SparkPeople if you need ideas, but try not to worry too much about creating the perfect program.
Hope that helps,
"You may have a fresh start any moment you choose, for this thing that we call "failure" is not the falling down but the staying down." Mary Pickford