Continuity mistake: Peggy's shoes go from purple to white in one shot in Nancy's kitchen.
Other mistake: Dale laughs at Nancy for picking up the diazinon, instead of the bird repeller gel. He then picks up a bag, goes up the ladder, and when he turns the bag around, it says diazanon on the bag he picked up. The only gel in the scene was what Nancy picked up.
Answer: If you are talking about the "Thou shalt not do this, thou shalt not do that" song, I'm not sure if a song like that actually exists. Green Day, the guest voices on the episode, might have just been improvising to keep their appearance from being too obvious.