Door to Door (2002)

This inspiring made-for-cable movie tells the story of salesman Bill Porter (William H. Macy), who came into contact with many people during his decades of knocking on doors. Porter, suffering from cerebral palsy, didn't allow his condition to stop him from pursuing a career, and his story touched the hearts and lives of many of his potential customers. Macy also collaborated on the script with director Steven Schachter.  2002   91 minutes

NY Times Review

Also see Jessica Yu's excellent 1999 documentary about the life of  Mark O'Brien.