Any way to disable keyboard and still watch DVD?

Hi. I have a new aluminum macbook pro, and I wanted to know if there is a way to disable the keyboard so my baby can watch a DVD on the plane without the worry of him accidentally hitting the keys? Thanks for your help.

 

I was thinking that there might be a program or a way of setting up a keyboard shortcut such that a specific combination key strokes can restore keyboard access.

 

Thanks guys... I tried Keyboard Cleaner but it gives me a black screen which means that I can't watch a DVD while it's activated. Thanks for the suggestion though.