Look in the Control panel under Mouse. Click on Device settings. Your Touchpad should show up there in the Devices listing. High light the device, now you should be able to click on the Disable button. If for some reason it is not listed there, Contol Panel/System/Device Manager scroll down to Moue and Other pointing Devices. Click to expand and your touchpad should be in there.
I am on bedrest and so am stuck using my husbands laptop for internet access. While it runs fine, it is annoying the heck out of me with the "scrolling" it does. Every now and then when I'm tying or using the "mousepad" (the little pad IN the actual laptop) my screen will start to scroll up or down. I realize that I must be using/rubbing the mousepad in such a way to cause it, but I wonder if I can "lock-out" that feature somehow. I don't even know exactly what the feature is, so I'm having a hard time looking for answers.