Download TouchFreeze. This freebie shuts down the pad when you begin typing. If it doesn't work with your pad, search the web for other programs like it.
I don't see anywhere in device manager where I can disable my touchpad. I do a lot of editing and the touchpad gets in the way of my palm and sends the cursor flying. Can't deal with it. I have an external mouse and when plugged in it works, but touchpad still on also, so not fixing my problem