Over the past few months, my Windows XP machine has slowed down to a crawl. It takes about 10-15 minutes to go from power-up to reaching a responsive state. I have reasons to believe that this is a result of the hard disk slowing down. Questions:

• Do hard disks slow down as a result of mechanical wear and tear ...or age?
• How do I check if my disk has slowed down? Conversely, how can I verify that my disk is indeed running at the speed it's designed to run at?
• Could drivers be at fault here? Do hard disks come with drivers or does Windows use a generic driver?