CASTLING

Is castling to the queen side not a better option as one avoids being trapped behind his own pawns without wasting a move in advancing his pawn also the queen side rooks comes to a good position this way.

Castling depends on the position.  

Part of the idea behind castling is to get your king safe.  That is the idea of the pawn wall in front of your king.

Queenside castling leaves the a-pawn defenseless unless you move it or move your king to defend it--meaning you still need an extra move for safety and breathing room. Both sides have their advantages and disadvantages, and while kingside often works out more conveniently, the most important part is to be able to recognize which is better in a given situation.