Instead of corn cob curtains, Marge has corn cobs hanging in the corners of windows by ropes.
Among the heads visible on pikes are Bleeding Gums Murphy (who died earlier in the series) and Troy McClure who stopped appearing when his voice actor, Phil Hartman, was killed in real life).
On the doctor's shelf, you can see several potions from various movies and video games including Polyjuice potion (Harry Potter), Mudane Potion (Minecraft), and red, green, and blue potions that cost various amounts of rupees (The Legend of Zelda).
The recipe for P. Jackson's overstuffed hobbit is: Cut hobbit into three pieces; pack with unnecessary stuffing; serve many, satisfies none.
When Marge and Homer refers to the sideburns of Ned Flander's impaled head as looking,, "Pretty, pretty sharp." it is a nod to Larry David in Curb Your Enthusiasm.