I was just wondering what easiest way to approach this problem might be. I need to open a window, say 500 x 500 pixels large, with each pixel turning on or off given a command.
I'm guessing I'll need to use something like openGL? Any simpler alternatives?
Well, your description can be fulfilled by a simple window 500 x 500 that handles the WM_LBUTTONDOWN and WM_LBUTTONUP window messages. No need for OpenGL or other graphics libraries.