To clear up, on what machine will this 'emulator' be running? (i.e. computer, game console)

What will be the controller(s)? (i.e. keyboard + mouse, game console controller, etc)

Will you be writing the emulator for these games/consoles, or will your program solely consist of a GUI to select one of many games (and call an external program to start the emulation)?
(if the former, I think you're in over your head)



Will respond more thoroughly after the above is clear.