Crazy Mouse

of course, if it's the windows being stalled completely due to hardware issues, the "mouse being stalled" will only be a symptom, and the issue is on the computer.
if it's a desktop, check out if you have too much dust inside your box. open and vaccum the box, check if ventilation is working ok, nothing overheating etc ...

How do I update the mouse drivers?

http://www.ehow.com/how_6784063_can-update-mouse-driver_.html

Try booting with a live CD such as Knoppix and see if the behavior changes.  If the mouse works you will know it isn't a hardware problem with your mouse.

http://www.knopper.net/knoppix/index-en.html

Connect the mouse to another computer and see if the problem follows the mouse.

Also, if it's a USB mouse try a different port.

Are you using it on a shiny or glass surface? I've seen optical mice do this on glossy or glass top desks because it reflects the light and screws with the operation. Try getting a few pieces of paper to use as a makeshift pad and see if it works any better.

Make sure there is no obstructions in the optical area such as a hair