Not a smoker...What do you mean about the windows being "frosted over"?
Could it be tar from a smoker? Spray some glass cleaner or Simple Green or somethign on the interior and try wiping some off. If the cloth comes back yellowish brown, it's probably smoker's tar. It will come off, but with a lot of work.
simple green? i didnt even think about using that... haven't heard of that one, but i'ma try that for sure. thanks!!!