Laptop Touchpad Click Button Issues

I recently inherited a Dell laptop for work. It is a P8400 Intel Core 2 Duo, Windows XP Professional, Version 2002, Service Pack 3. Really strange issue with mouse clicking. When I click the left mouse button, it acts as if I am clicking the right mouse button. When I click the right mouse button, it does absolutely nothing. I tried going to mouse settings and switching the buttons, no dice. Tried uninstalling drivers and restarting, no dice. This is not an issue at all when the computer is docked and I am using a USB mouse. Bizarre and annoying. Any help would be much appreciated.