Hi Robert,
Thank you for reaching out to the Microsoft Community!
I am sorry to hear that you are unable to disable Touch Pad in Windows 8.
I can understand the inconvenience you have experienced. I will certainly help you out with this issue.
Let’s try these methods and check if it helps.
Method 1: Download and Install the latest touch pad drivers from the manufacturer’s website and check.
You can install Windows 7 drivers in compatibility mode if there are no Windows 8 compatible drivers.
Follow these steps:
a) Press the ‘Windows + W’ key on the keyboard.
b) Type compatibility in the search box and then press enter.
c) Click “Run programs made for previous versions of Windows” option from the list appeared in the left side.
d) Select the drivers and install.
Once you update the latest drivers, try to disable touch pad.
Method 2:
Press ‘Fn’ + ‘F3’ key to disable or enable the Touchpad on your computer.
a. Click “Start” and type Device Manager in “Start Search” to open the “Device Manager”.
b. In Device Manager, click on the arrow beside “Mice and Other Pointing Devices”.
c. Right click on “Dell TouchPad” and click on “Disable”.
d. Select “Yes" if you receive a warning message.
e. Close the “Device Manager” and check the issue.
If the issue persists or you have any further questions on Windows, please do not hesitate to let us know. It is our pleasure to be of assistance.