I went out and bought it today. Pretty great movie. Some argue it doesn't really have a plot, but even if that's the case it has amusing writing and fun acting. It's an entertaining movie to watch.
I live two hours from Preston, the city in which the film is based and where it was filmed, in a city called Jerome. Jerome is small and crappy and not unlike Preston. There's alpaca and llama farms around, and dairies, and people one might consider trashy like Uncle Rico and Napoleon Dynamite and Kip Dynamite and a lot of Mexican immigrants. Notably, though, there's a lot of people into punk music, and a lot of ordinary people that wouldn't be inclined to have photos taken at Deb's Glamour Shots--people that shop at Abercrombie & Fitch or American Eagle and all that.
I don't think Napoleon Dynamite is mean to its characters. A lot of people around here act not unlike that, and dress not unlike that, etc., but Napoleon is unapologetic, even blind to the notion that one should be apologetic or not. Sometimes people criticize it for just putting Napoleon and the rest of the cast up for ridicule, but they're absurd characters taken to be dumber than they are. I read once that comedy is when characters are portrayed as dumber than people actually are, and I at least laugh at Napoleon because I see myself in his naivete and problems related to not having a car and having embarrassing relatives. I mean, my brother chewed tobacco, my mom would sometimes buy irregular pieces of bacon to panfry, my dad likes NASCAR and bad action movies...
Oh, I dunno that I've really developed a full justification for laughing at the movie. But I do laugh at the movie, and if I ever met Napoleon, I'd buy him some tots.