I remember watching a movie on HBO a couple of years ago. It was about a small town where a guy works out in a diner. The diner has attempted robbery but the owner stops the robbery. The owners picture gets put in the paper and his secret past is revealed. His past was that he was a goodfellow or hitman for the mafia. His wife and kid become in danger. They are not aware of his past. Someone please help me with this title.

A History of Violence (2005) (http://www.imdb.com/title/tt0399146/) ?

Yes, that is it, Thank You!!

You're welcome.