Time to resurrect this thread, as I had the same problem occur today.
I booted my computer up this morning, got on, watched a few TV shows, did my morning Facebook routine and what not.. and my computer started to get really slow. Well I was watching my CPU performance, and it never got above 30 - 40%, so I couldn't figure out what was making it so slow.
So I figured a reboot might do the trick.
Reboot, and get the disk read error.
Well, I then had to reset everything to defaults, and reset CMOS to get back into Windows.
So I understand how to fix the problem, but I need help figuring out what is causing the problem. It's annoying to open this thing up all the time.