There was a movie about a rich family who are shipwreked on an island - the head of the family is a useless aristocrat and the butler takes control of the family and saves them only to return to status quo when rescued.

The Admirable Crichton (1957)
aka Paradise Lagoon
IMDb synopsis:
Lord Loam has modern ideas about his household; he believes in treating his servants as his equals~at least sometimes. His butler, Crichton, still believes that members of the serving class should know their place and be happy there. When the Loam family are shipwrecked on a desert island with the self-reliant Crichton and lady's maid Tweeny, the class system is put to the test.

Paradise Lagoon (1957) - IMDb (http://www.imdb.com/title/tt0050100/)

A number of versions of the story have been filmed. Here's a page with links to the others:
http://www.imdb.com/find?q=The+Admirable+Crichton&s=all