Which opening will develop both bishops like the following diagrams? I'm looking for a chess opening that would result in something similar to the following end-positionings: 

A nice open diagonal for the bishops.



or maybe the other way:



Also, what are the strengths &amp; weaknesses?
Danish Gambit is a possibility. There is no free lunch, no strong players will allow you develop your bishops like what your described without any compensation. You will need to gambit two pawns for this line.

From wikipedia