If you can get to the menu's find the mouse/touchpad settings in the
system-settings. You can also talk to it via the command-line using
synclient. So for instance
synclient TouchpadOff=0 could switch back on the touchpad (if that was causing it). If it doesn't work or it complains with some errors, try to unload/reload the driver:
I made a small script that I've put in
~/bin (for instance
reset_mouse) and made executable with
chmod u+x ~/bin/reset_mouse. This is the script:
xterm -e "sudo modprobe -r $device && sudo modprob $device"
You might have another device (this is mine on my Macbook Pro 6,2). You can Google it or search via
Hope this helps.