If your mouse not working and want to shutdown your PC or do any other work.You can enable the accessibility feature to move the mouse using their arrow keys by following the below steps.
Click Start ->Control Panel.
Within the Control Panel open AccessibilityOptions or Ease of Access
Click the Mouse tab.
Check the “Use Mouse Keys” check box.
If you wish to increase the speed or change any other settings, click on the Settings button.
Click Apply and then close out of the box.
After performing the above steps you will be able to used the numeric keypad as a mouse moving up, down, left,...