The Ghost and Mr. Chicken (1966) on Netflix

Luther Heggs is a jerky, quirky typesetter for the town paper who aspires to move up from his basement office to be a full-fledged reporter. He also pines for town babe Alma, who's already seeing the newspaper's main writer, Ollie. The film is centered around the Old Simmons House, which is known as a "murder house" around town due to the murder/suicide of Mr. and Mrs. Simmons 20 years earlier. Rumor has it that you can hear the ghost of Mr. Simmons playing the organ at midnight. To boost newspaper sales, Luther is assigned to spend the night in the house on the night of the 20th anniversary of the murders. All is well until midnight, when Luther sees the old organ begin to play by itself (the film's title tune is used in this and other scenes). His story makes him the town hero until Nicholas Simmons, nephew of the deceased couple, sues Luther for libel. In the courtroom, Luther is made to look the fool, but the judge orders the courtroom to the Simmons House at midnight to allow Luther to prove his story. Nothing happens, of course, but after everyone except Luther leaves, the old organ begins to play and he finds Mr. Kelsey, the newspaper's janitor, tickling the keys...