Hey there:
What about Logan's Run (sci-fi from the '70's, one brief scene of nudity with the main character having to change wet clothes) which could provide an interesting discussion on mind control and beliefs about the world "outside". Google search this site for more info on that.
National Tresure showed masonic imagery--you could tie in Russell's early WT symbols (use the photos in the Proclaimers book)
What about stuff on the Mormons or other cults? There is a scene in the movie Bee Season with the son of the family being recruited by the Moonies. (I found the movie to be disturbing in other ways).
Talk about cults, and how they control people, don't let them think outside the box. There was a film recently on tv about polygamous Mormon sects and people trying to escape. I think there is a tv series about a guy with a couple wives, but haven't seen it.
TS