Good to hear, Papa. The question I would ask is "where do you want to start?"
I'ld see my doctor asap, as he'll more than happy to help you with the smoking, and to get your asthma under control.
I don't know how had your knees are, but CG's knees are bad too IIRC and he rides. Walking and swimming were my two poisons of choice.
Drinking occasionally shouldn't be a problem IMO
As for the black belt, put it back on before your pants fall off.
A couple of interesting motivational reads are Body For Life and Body By Design.