Comment 7 for bug 386980

Log in to your Ubuntu box (you can do this without a mouse).

GNU/Linux is easy to use without a mouse if you know a couple of keyboard commands.

Press ALT+F1 to pop up the menu.
Use the arrow keys to navigate to
Applications->Accessories->Terminal
When it is highlighted, press ENTER and a terminal window will pop up. Press ALT+Tab to go to it, but it should already have focus.
Now type in the terminal:

$ sudo apt-get remove xserver-xorg-input-synaptics

a lot of messages will pop up in the terminal and it will ask you if you want to remove the package (as well as xserver-xorg-input-all). Enter Y and press ENTER.
The packages will be removed and your mouse will start working.
Now be glad you have a (powerful) command line and learn how to use it!!!