Weight training builds muscle, muscle burns fat. Combining cardio (walking = approx 100 calories per mile IIRC) and weight training is the way to go IMO, but I'm just a layman at this, no fitness/health expert.

From what I've read, Roman Centurions typically ate only dinner and therefore went all day on their stored energy. Typically, I eat breakfast so my work-outs burn energy I just ate. I'm thinking on that Centurion lifestyle as a possible way to drop some pounds.