I know this is a toughy...and let's not mention some cheap, penciled 2 minute movie you sat through like Godzilla meets Bambi, I'm talking feature length, animated film.
I'd have to say its between Pixar's Cars and Disney's Treasure Planet for me. But at least I managed to sit through & finish Treasure Planet, so CARS is the winner on my list as worst (I still can't sit through this redneck themed POS).
Since I know there are a lot of Pixar fanboys on this site, let the flaming begin.
What's yours?
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Recent:
Sueño (2005): 7/10
The Tripper: 6/10
Horton Hears A Who: 9/10