Windows 7: DPCs and Problems Shutting Down

I noticed that whenever I try to work with a DVD that is scratched, that the CPU usgae spikes. Process Explorer indicates DPCs accounting for >60% of CPU usage, and I have to assume that this is related to the problems with the DVD drive not being able to read from my DVD.

However, I cannot get the CPU usage to go down, even after removing the DVD and closing any software that I was using with the DVD. Does anyone have any suggestions how to stop the DPCs and Hardware Interrupts and bring the CPU usage down?

Also, if I try to reboot after I am in this situation (a necessity so that the computer can run smoothly with low usage), the shut down freezes and I have to do a hard power down at the PSU. I am assuming that the DPCs and Hardware Interrupts have something to with that.

Ya, I notice similar problems when trying to read a defective disc.

Only solution = power down, power back up.

You could try using this - http://www.majorgeeks.com/download2623.html

Or you could sand the bottom of the disc with white toothpaste and your thumb, going from center to outer edge. If you remove enough of the damage this way, this disc could then be read well. Make an .iso of it if possible, then throw out the original

I never noticed this in XP. Is there a reason why the Windows 7 reacts this way to a bad disc?

Also, is it normal that shutting down is a problem (it freezes on the shut down screen) in this instance and that I have to power off at the PSU?

Yeah, because explorer.exe hangs and can not be closed, even by the OS itself when it tries.

It's just how it is.