I don´t know the name of the episode, but it was April fools and Homer kept tricking bart over and over again until Bart decided to get revenge... He gets the last beer in the fridge and shakes it like crazy, even with a paint mixer machine and places it back in the fridge (meanwhile the can is vibrating still). When Homer goes to the fridge and grabs the vibrating can, he begins to open it and Bart turns the corner to say April fo... *BOOM!!!* the whole house blows up. hahaha

I like the one where he tries to keep Bart from turning gay he took him to a steel mill to see some "manly men" and during breaktime it turned into a gay dance club.

There are so many...how about tree house of horrors X. It's the episode where Marge ends up running over Flanders one night, it is kind of a stab at I know what you did last summer...only it doesn't suck.

yeah that medical mj episode was funny - mostly because you know the writers are stoners to come up with those specific references they made.
But my all time favorite is Homer vs. NY City. Mostly because after 9/11, it wasn't aired again until either 2004 or 2005.