"Fart" does in fact mean "speed" in Danish.
This episode has Homer make a speech based on Shakespeare's Hamlet (known as the Dane).
There was no mention of Abe's other tattoo (Hellfish), showed on Raging Abe Simpson and His Grumbling Grandson in 'The Curse of the Flying Hellfish' (1996).
The line which Edna Krabappel speaks is taken from 'Bart gets a 'Z'', as the actress who provided her voice, Marcia Wallace, died years before.
The title is a reference to "Throw Grandma from the Train".