I own all of them myself, my favorites have to by "Parasites Lost", "The Why of Fry", and the one where the globetrotters come down to earth the name of which I can't remember right now. I think my least favorites were "The 30% Iron Chef" and the one concerning Fry's "human horn", that aside from not being that funny, was the second to last episode and thus a major let down. I also think that the one where they all get youthesized is a good episode, but it's kind of overrated.
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Your boos mean nothing, I've seen what makes you cheer.
- Rick Sanchez