Drivers don't usually just stop working at random. USB devices generally do not need drivers to work. Drivers just give them more options or make them work more effectively. But, you should be able to plug pretty much any USB device into any computer and it should work, especially mice.
Have you tried any other USB devices (flash drive, keyboard, camera, etc)? Have you tried a USB to PS/2 adapter on your mouse?
EDIT: Welcome to the forums by the way.
