episode name is "So Its Come To This - A Simpsons Clip Show", but there's some original stuff here... Homer blindfolds Bart in bed and tricks him into drinking 6 month old milk for april fools... Bart gets back at him by shaking up his beer so much that it causes an explosion and puts Homer in the hospital...
"Mrs. Simpson I'm afraid your husband is dead."
"Heheheh, april fools. But he may never walk again."
an obscure doctor from an earlier episode comes in to explain Homer's condition, and Marge shows clips of a bunch of earlier episodes explaining how his body got so messed up...
later he gets memories of that "Land of Chocolate" daydream.. then he manages to get up and walks over to the candy bar machine, knocks it over on himself and has a bunch of chocolate fall into his mouth.. now he's in a coma..
Bart telling Homer that he's the one who made that beer explode, made him instantly recover and start choking Bart... later they all laugh off the fact that he's been in that coma for 7 weeks and he lost 5% of his brain.