The scenes with that Joel dude
I believe it was from Season 4, episode 6, where Kenny and Stevie were looking for a big guy to intimidate Guy and they found one in choir. He seemed very off and couldn't deliver his "dialogue" right when confronting Guy. I don't know why, maybe it was the total randomness of it all, but I cried from laughter for about half an hour.
"We all go a little mad sometimes"
Anthony Perkins as Norman Bates - Psycho (1960)