Saturday, August 7:   Family Movies @ Your Library presents “Diary of a Wimpy Kid”@ 2:00 pm.  The first volume in Jeff Kinney's wildly popular Web and book series hits the screen in this live-action      adaptation.  Greg Heffley enters middle school determined to become class favorite.  It won't be easy.  His best friend is a big, redheaded lug who embarrasses him at every turn.  Greg's obnoxious teenage brother advises him to keep his head down.   After a humiliating encounter with some high school bullies Greg learns what really    matters: self-respect.  Rated PG.  (94 min.)