To open a show, to open a series, a franchise, a corporal medium to the world requires a lot. It means to allows every single character to be introduced, obviously not properly, but so much so as to let the audience become familiar with them all. What "Simpsons Roasting on an Open Fire" does is let the dynamics and ideas flow over you as water, as a brisk Christmas Eve in 1989, letting you into the world of Springfield and the Simpsons. The episode has it's cliche and somewhat sporadically cringey moments, but aside from that, it's a fantastic opener.
