How can I stop Front Rew kicking with ATV remote?

I have all new kit and trying to work out how to avoid the Frontrow or iTunes on my iMac reacting to the remote while directing the ATV2 device.

Does anyone know how I can do this?

I have tried shielding the signal which worked with the previous version ATV (1) and remote but not this time.

(I do not really need to use the remote for the iMac but would in future like to be able to switch on or off for use with iMac.)

Thanks for any help!