Which arduino board would you recommend?

babipsylon:
So, maybe I reformulate my question: what's the easiest board to:

program easy instructions
have output to the motor
have option to power off the motor via the board

Any Arduino board will do that.

But you cannot connect a high-power device like a motor directly to an Arduino. You need a h-bridge or motor-driver-board in between the Arduino and the motor.

what accessories do I need to connect the arduino to my computer in order to program it?

A USB cable - and the Arduino IDE (programming software)

...R