Comment 295 for bug 550625

@Brian,
Not completely true. When you're running Windows and in the BIOS you have selected to disable the touchpad when an external mouse is connected, the stick will still work but the touchpad won't. Mario just wants the same behavior, without actually attaching an external mouse.
It is true that on Linux, the same module/driver is responsible for both touchpad and stick and without some further research, the easiest and quickest method is indeed opening the case.

@Mario,
Have you checked the BIOS settings for that? Maybe you can disable the touchpad on it's own from there.