which of the 2 minor peices is better?   is one of them better or does it depend on the position?

it depends on the position.

totally depends on the position!

It accually depends on where the game is at if the board is cramped you would like to attack whith the knight, but if the board is open your bishop should attack.

My Saying is ( Start With Knight End With Bishop! )

Knights are more powerful during openings and midgames where bishops tend to shine during endgames.