My DS5 is a huge Pixar fan (Toy Story, Monsters Inc, Nemo, Incredibles), has loved the movies for several years, especially TS 1 & 2 and its characters. We have the DVDs (and Disney ones like Aladdin, another huge favorite), toys, Disney books, books on tape, etc.
I also wanted to familiarize DS2 with the Disney characters (he loves Pooh characters and Toy Story, but other than that hasn't seen a lot.) So I borrowed movies from my mom and sister (Cinderella, Snow White, Beauty and the Beast, etc.), but they aren't as interested in those, apparently not enough action in the princess movies for them! We've also been re-watching the favorites, of course.
They also love the planning DVD, I have never seen them so intent on what is basically a long commercial! It was kinda cute.
Here's hoping they are familiar with many of the characters by our trip in September!