steve, for me, lifting weights 3 times a week helped a lot. while i was never really overweight, i was what you'd call skinny fat or out of shape. my energy level's improved, strength obviously but most importantly, i've been able to get my body fat % down. i don't do cardio - i'd rather poke my eyes with a rusty screwdriver than sit on a stationary bike for 40mins.
nothing extreme - goo a doogle for mark rippetoe's strength training - i basically do his routine. 30-40mins every two days. don't make the mistake of thinking more is better with weights - you body needs time to rest and regenerate. don't do it every day!! muscle burns calories even when you are sitting on the couch. by increasing your muscle mass, you are speeding up your metabolism.. making it easier to lose weight.
in terms of diet, i've cut down on "bad" carbs - no white bread, white rice, potatoes etc. whole wheat and brown rice are ok. someone mentioned fruit juices and tehy are absolutely right - loaded with sugars.. they are NOT the health drink some make them out to be. meat and veggies are the staple here with more frequent, smaller meals. i do supplement my protein intake with shakes.
I think people get hung up on weight when they should be more concerned with BF%.