For any GUI work you will save yourself a lot of headaches to use either C++ Builder or Delphi instead of MFC (The Borland VCL libraries are vastly superior and much better integrated with the IDE).
However for the raw computations in your image recognition code, VC++ has much better compiler optimizations to make it run faster, so maybe use that to make a DLL to do the core calcs. Or better yet, use the Intel compiler.
BTW the bitmap is already a 2 dimensional array of pixel colors within the file (starting off with the 55th byte for a truecolor bitmap, 256 colors is more complicated because of the pallette), but you are probably better off using an existing library to parse the header info and determine resolution/color depth, etc.