Ghost Town (2008)

Bertram Pincus, a cranky, people-hating Manhattan dentist, develops the unwelcome ability to see dead people. Really annoying dead people. Even worse, they all want something from him, particularly Frank Herlihy, a smooth-talking ghost, who pesters him into a romantic scheme involving his widow Gwen. They are soon entangled in a hilarious predicament between the now and the hereafter!