Every so often, your computer may just LOCK UP.  You don't have a mouse function.  You're just STUCK.  Your jaw drops.  A trickle of slobber develops in the corner of your mouth.  There's only one thing to do--right?  You gotta shut it off, no matter how many windows are open. 

WRONG !

When this happens--and I promise you it WILL HAPPEN--tap the key next to your CONTROL key on the left side of your keyboard.  This will bring up the START MENU. 

Use your Up and Down Arrow keys to highlight START.  Then click ENTER.  That brings up the Shutdown Screen. 

Use the Arrows once again to highlight RESTART.  Hit the ENTER key again.  Your computer restarts.  In all likelihood you won't have to sit and wait while your computer does the SCANDISK thing which results from a power switch shutdown like you've probably been doing when you get in that FREEZEUP situation.