Chuck is right, the only way to really get the fat burn is to build muscle. Bigger muscle burns more fat even during resting periods. If you can't or don't want to do the gym now just do push-ups, sit-ups, squats, ect. A good form pushup requires your arms to "bench" roughly 70% of your body weight.
I suggest going to GNC or Sears and getting the pull-up bar they sale. It's like $30 and you can do different styles of pull ups on the door frame (it holds my fat self), then you can turn it over for push-ups, dips and sit-ups. Toss in some 5 lbs. ankle weights on other exercises and you are good.