This story is predictable and is nothing new - the classic story of a rag-tag group of misfits who are led to victory by a dynamic personality. But... it works. It works really well, mostly because it rides the coat tails of the highly successful and imaginative "Monsters Inc."
As a prequel, it was fun to see how this movie related to "Monsters Inc." The jokes were spot-on funny, and the university environment was a cool backdrop for this story that was different enough from the scare factory to feel like it was something new, and not just a re-hash of what was done 10 years ago.
I highly recommend this movie for families. Pixar knows how to engage all demographics simultaneously and is refreshingly able to avoid rude humor while still delivering top-notch entertainment. Kudos once again to Pixar.