Welcome to SparkPeople! I have been a member for a while, but have only just begun using SP for all that it is worth. Tracking your food is essential for loosing weight. I have also found much motivation on the fitness front and went from thinking “I need to loose weight”, to “I need to get fit”. The difference in attitude has improved my overall outlook. I owe a lot of that to SP.
Do not get overwhelmed. Take it slow. Find one or two groups that fit your goals and get to know the people in the group with you.