Thanks for referral to the manual link, which showed no hot key to disable the mouse track pad.
I went to support chat on gateway and got some surprisingly incompetent people. One disabled my external mouse instead of the track pad. Finally one of them told me there is "no way to disable the track pad". That may be the "party line", but I refuse to accept such an answer. You would think they would have an electrical engineer who might even have learned something in engineering school. Unfortunately the chat guys are NOT engineers and can't be bothered calling one.
Someone told me a firm called Synaptics makes these and has software which can help. So far, though, I went on their web site and can't find it. I may have to try the "bigger hammer" trick to disable this furschlugginer mouse pad.