"To hate" is not the most accurate word for it, but I always really disliked A Star Is Burns and SimpsoncalifraglisticexpialaD'ohcious for the same reason: both episodes just don't feel as an episode of The Simpsons. In both of them, The Simpsons Universe adapts at the other series when it should be the opposite. I don't have problems with crossovers nor with parodies/homages particularly (The Springfield Files is one of my favorites episodes and I don't know anything from The X Files). But I have a real problem when I feel I'm not watching The Simpsons, when neither the story nor the jokes nor the characterizations fit in the episode. A Star Is Burns is an episode of The Critic with a guest appearence of The Simpsons and SimpsoncalifraglisticexpialaD'ohcious is a -bad- Disney movie that elapses in Springfield. But nothing else.
I obviously hate Another Simpsons Clip Show and All Singing, All Dancing, since both of them are two of my least favorite episodes of the show. And yeah, this time is to hate the actual word. I dislike them at the point that I've never watched them completely without interruptions (something that only happened with Politically Inept with Homer Simpson too).