Descent 2nd edition always seemed like a good game that could fit right in with this feature. Each quest takes about an hour and it's a game that would look good filmed in my opinion
The rules are pretty easy and the game plays well with a group of at least 3. I always have a blast playing it. However, the nice thing about a table top RPG is that the DM can fudge rules to make things flow and make things interesting. If you don't have someone in a group that's familiar with the Descent rules, it might not be horribly fun to watch. Also, watching others play will make me want to play, which I can't do right now because everyone I know who's interested has been too swamped for gaming. I just finished up painting up the main box miniatures, too.
I guess it all really boils down to interaction. If the Pathfinder series was Neverwinter Nights, Descent would be Diablo. Then again, it seemed like it was Vinny and Dave who brought the bulk of the role playing into Pathfinder, and they left some mighty big shoes to fill. Maybe straight up dungeon romping for loot will fit Unplugged:TNG better.
But for easing back into Unplugged, I think King of Tokyo would work real well. The rules are incredibly simple to learn.