Your mouse problem is more likely the mouse than the compuer. We find the optical mouse to be absolutely the highest failure item for any computer. A friend who works at Wal-Mart says the optical mouse is their highest return item. I seriously doubt you will be able to fix it. Go back to a PS/2 mouse if you can, and your troubles will be over. Borrow another mouse to be sure. If you use a non-optical mouse and it works, and other equipment works on the USB port, then you know it is time to toss it.
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