Whistle While Your Wife Works - S5-E5
Other mistake: When the guard is turning the vault handle, the handle doesn't move, but the guard's arms do.
Airport '07 - S5-E12
Other mistake: As Quagmire sits at the bar, Hugh Hefner comes and gives him a pep talk. During it, he says John Holmes said Glen Quagmire is the best pilot. Unless he had seen the news or knew him personally, Hefner couldn't have called Quagmire by name.
Boys Do Cry - S5-E15
Other mistake: Towards the very end, they automatically head to the car, planning to leave Texas, without any of their items from the house packed in the car after running away from the mob at the Miss Pageant Contest.
Other mistake: Peter goes back in time and sees Lois at age 18. Death says everyone will see Peter as being 18 too. Problem: Lois and Peter aren't the same age. In later episodes, Lois reveals she's 2 years older than Peter so Peter should be 16 when he meets Lois.
Chosen answer: It's a real song called "Elvira". Originally by Dallas Fraizer in '66, however, this version seems to be the Oak Ridge Boys cover version. However, the mega lesbians skip the verse and just sing the chorus after the opening line.
Bishop73