Dan,
I'll write this here for the benefit of anyone else with the same problems. Disabling the mousepad:
There seems to be three ways of doing this. The first and the most helpful is to reduce the sensitivity of the pad, which is within the control panel / mouse settings.
The second is a physical disable which will be within the BIOS code, which frankly unless you do the whole computer coding thing, all seems pretty Greek to me.
The third and most ugly is to cover the pad with a small piece of card and tape it down. But at least it works.