numpad interface with microcontroller

hi.....
i want to know about the interfacing of numpad with microcontroller.........
i want to install it on vehicle with my transmitter........
so which one should i select for this pic or 8051.......
kindly help me in this decision making process........

It sounds like you have no experiance with micro controllers or programming.

If that is correct your project is too advanced. Walk first, then run.