I am planning to write a game for the iPhone, I am coding it, my friend is doing the art work. I am not sure about the graphics, the view will be from the front, it will be like a mortal kombat style game. Is OpenGL ES the best for this?

What is the best way to supply the art, lots of different drawings for the different movements like animation?

I was thinking of loading the background image like the arena, then just load the images for the characters and depending on the buttons pressed the appropriate images load, is this correct, or please explain a more efficient technique or maybe a good reference.

Thanks in advance.