According to Entertainment Weekly, the top sketch of the 20 top sketches on Monty Python is --The Spanish Inquisition! -- No one expected that....

The Dead Parrot is, I think, number 4, which seems a bit low. I would have it as a tie for first. Two others missing in the top 20 are the Cheese buying scene, and my favourite, the   race that includes untying the brassieres from the dummies.

yours,

Peter T.