Just a couple of moments that always come to mind for me:
Homer: This will teach you, you stupid chair.... AAAAGH! I'M ON FIRE
Marine: Anything for an ex marine!
Homer: Semper fudge
Marine: Err, did you just say semper fudge?
Homer: Nooo, I said the right thing
Homer: English instructions covered in cement, must use French....... la grille? What he heck is that supposed to mean?
Homer: Who wants me to drive through the cactus patch?
Bart: Yeah!
Lisa: Yeah!
Sideshow Bob: No!
Homer: Huh, 2 against 1
Special mention to the fade to black of Sideshow Bob reapeatedlly stepping on rakes. I'll still be chuckling to the Thwack sound, followed by his groans on my death bed