Factual error: Donna was killed by a falling cell phone in 1982. The first cell phone in common usage was the Motorola DynaTAC 8000x, which came out in 1983.
Factual error: Pete died in 1984. Yet mentions the movie 'Ghost' with Patrick Swayze which released in 1990.
Suggested correction: It is established that the ghosts have watched television, listened to the radio, smelled pizza/pepperoni, etc. It's not impossible that Pete saw Ghost on TV.
While they do watch television now, it's unlikely that Sophie watched "Ghost" and that Pete saw it alone. The reply from others was "you know we don't know what that is" and he said "oh, right the movie thing." Which was a call back to earlier when Trevor was trying to explain who Tara Reid was and the older ghosts had a hard time knowing or remembering what a movie was.
Factual error: The ghost doctor says he's been in that building for 85 years, meaning he would have died in 1936, but the stethoscope he wears was developed in the 1970's.
Ghost Father of the Bride - S2-E19
Factual error: Crash is shown sitting in the TV room at night, but he is watching The Price is Right which is on in the morning in the north-east.