Geek! :’) It’s better to have the switch, in case, for example, I didn’t have a mouse with me. And having to go into BIOS to do it is really [singing] from the, town of Bedrock...
So.....when you are using an external, USB mouse, click on “Start”/”Control Panel”/”System” icon/”Hardware” tab/”Device Manager” button for “Windows XP”,/( “Control Panel”/”System” icon/”Device Manager” icon in “Windows 7” )/In the “Device Manager”, look for the “Mouse and other pointing devices” branch in the tree/Click the plus sign, ( + ) to the left of that branch and find the scratchpad/Right-click on it and click on “Disable”.
When you need the scratchpad then you can reverse the above by clicking on “Enable”.
Think outside of the box! ;-)