sodaseller -- that sounds fantastic...I've never been to a convention or a Celebration, but I'd love to go...I hope he's there one weekend, I'd love to see him!
As for the Trivia Challenges, the table is between Indy and Star Tours. I think you can sign up throughout the day, probably from 9am on, but people were still signing up as late as 2 or 3 o'clock. We didn't see the Padawan show, although I think (I can check the schedule, I just don't have it on me right now) there are two different times for the Padawan trivia, as opposed to one showing for the adult.
and xanthefan, I never tire of talking about Star Wars...if you have any more questions, I'm more than happy to answer them!