Who played Johnny Castle in 'Dirty Dancing'?

Who played Sandy Olsson in 'Grease'? In which film is Sandy Olsson a character? Who played Tony Manero in 'Saturday Night Fever'? In which film is Tony Manero a character? Who played Frances "Baby" Houseman in 'Dirty Dancing'? Who played Sam Wheat in 'Ghost'? Who played Oda Mae Brown in 'Ghost'? In which film is Oda Mae Brown a character?