The exact location of "Lanford, Illinois" was vague over the course of the series. But one scene offers the best clue when a radio announcer issues a tornado warning for eastern Fulton County (a real place, many rural miles west of Peoria), and Darlene exclaims, "That's us!"
Roseanne didn't enjoy waiting for the effects people to set up for the tornado. It took hours to do it, so while she was waiting, she thought up DJ's name, David Jacob.
Becky refers to her pet guinea pigs as Pebbles and Bam Bam, names taken from The Flintstones. John Goodman would go on to play Fred Flintstone in The Flinstones (1994) movie.