Well, I'm in college and tonight in my dorm's Sci-Fi/Fantasy group, we're watching Advent Children. Most of the people who are going to be watching it have never played the game, and I am responsible for providing them with enough background to appreciate the movie.
My question to you all is what should I tell them?
I think that the introduction of the movie effectively sets you up for knowing who Sephiroth is, what Shinra is, and the Planet surviving Meteor.
I don't think it's necessary to know the side characters' back stories, and by that I mean Cid, Cait Sith, Vincent, Yuffie, and Barret. I mean, I can explain Marlene by saying, "Barret adopted her - the end." "Denzel is this kid who has randomly showed up and lives with Tifa and Cloud and Marlene."
Mainly what I need to explain is Cloud's relationships with Tifa, Zack, Aeris, and Sephiroth. What is a good way to do this? (PS: We're probably going to hook my laptop up to the bigass TV, so I might be able to use images as a teaching device! I am so awesome!)