I've struggled with my weight as well, still am and probably always will - I just love food too much... but what I've been doing is adding exercize into my daily life. I've tried doing things like running, rollerblading, exercize routines... I always eventually overdo it, hurt myself, have to miss 'a day' which turns into 2, then 3, then I just never go back.
So what I've started doing is getting off 2-3 stops early on the bus and walking to work from there(works out to about a ~10 minute walk all told). Taking stairs in stead of elevators as much as I can. It hasn't had a huge impact on my weight just yet, but I FEEL a lot less out of shape, which is far more important, in my eyes. How you feel matters more than how you look.
But as the person above said, if you just want to 'get in shape' cardio is indeed what you need. Cardio and dietary changes.