A good opening for a beginner to learn ...

http://www.chess.com/forum/view/chess-openings/easiest-opening-to-learn-for-beginners

I would like to recommend that a beginner learn the Colle. Its one of the easiest openings to learn, and if someone is really a "newbie," than it might give them a good chance to play against a better (i.e., more experienced) player ... and at least give them chances to win. 

I have written a detailed article on this opening, you can read it on the WCA website here. 
(The "World Chess Academy" is now closed ... but you can view it on various web archives - here.)