1x6 - The New Scooby-Doo Movies

When the gang find a lost dog, they return her to her owner, Phyllis Diller. They soon learn that Ms. Diller's house is haunted, presumably by the ghosts of her deceased husbands.But is it really ghosts. . .or someone trying to scare her into giving out the combination for her safe, which houses her priceless jewel collection?