Don't let your wife watch something scary right before bed.
I did not make her do this but I let her do it. We watched a very creepy buffy episode right before bed and it gave my wife nightmares. Sometimes as a husband you have the be the voice of reason and take the lumps for looking out for you wife's best interests even if she doesn't want you to.
Had I not let my wife watch it right before bed we probably would have had a better night sleep.