Ah, I see the problem. I read "I guess whether they smoke or not it is their choice," (which...isn't even a sentence, but I digress...) as "it isn't their choice," and responded accordingly, but I'm guessing that's not what you meant. My bad.
Indeed. As for what is, or is not, a sentence, well consider THIS: "Is somebody holding a gun and forcing them too?" - the interesting use of the word "too". Unless, of course, you really do mean "too", in which case...well, you get the picture.
Anyway me and you should, perhaps, get out more; this is a message board and not some literary establishment :)