More of an easy tip than any kind of fix.
The trackpad on my Macbook is messed up and by disabling it in KDE I have made my laptop usable again. This is what happens when a 3 year old decides to do daddy a favor and clean his laptop with tooth paste and water. :|
To disable the trackpad when a mouse is plugged in go to: K -> Settings -> System Settings -> Input Devices
Click the Enable/Disable Trackpad tab on the right.
Check the box that says to disable the trackpad when a mouse is plugged in.