Someone I know had the exact same problem on her Compaq NX9005 ( I can't mention who - I can't afford a divorce ! ).
"Her" problem was caused by using a seperate PS2 mouse and not disabling the touchpad mouse, so as she typed away her palms were moving over the "live" touchpad which kept moving the mouse. On this laptop there is a simple button to press above the touchpad to turn it off, and I have now provided full instructions to the user on how to press it !
Simple mistake but hey - I love her really !
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