Lightning fast 2d engine specifics

Hi Could someone, anyone clear out what is the best way to create a 2d engine in directgraphics that''s ment for speed. As far as I can see, there are options: a) 1 vertex buffer with 4 vertices, each sprite is drawn on the modified vertices. The Z buffer is disabled, so you draw everything like in good old DirectDraw - on top. b) 1 vertex buffer with a selectable amount of vertices for each texture, each holds 6 vertices (4 if indexing is used) for each sprite drawn. The Z buffer is enabled, so we need to control the Z level also. c) 1 vertex buffer for everything, seperate index buffers for textures, same as ''b'' any other ideas? --- Keep it simple, stupid