MD23 motor controller

Hello, I bought the MD23 motor controller + EMG30 motors with encoders.

http://www.robot-electronics.co.uk/htm/md23tech.htm

my question is, how to interface with this controller? i have done some research and I think this is the adapter that will let me control the motor controller with the PC:

http://www.robot-electronics.co.uk/htm/usb_i2c_tech.htm

Also, I will be using an ardiono duemilanove to control later this motor controller, is that possible?

So I want to know if that adapter is OK for what I need, if not, what?

thanks