BSOD DRIVER_POWER_STATE_FAILURE ntoskrnl.exe

Welcome,
The driver named as the cause is disc.sys. This is a microsoft driver and not the true cause. Lets try verifier to see if we can find the cause.
Driver Verifier
I'd suggest that you first backup your data and then make sure you've got access to another computer so you can contact us if problems arise. Then make a System Restore point (so you can restore the system using the Vista/Windows 7 Startup Repair feature).

In Windows 7 you can make a Startup Repair disk by going to Start....All Programs...Maintenance...Create a System Repair Disc - with Windows Vista you'll have to use your installation disk or the "Repair your computer" option at the top of the Safe Mode menu .

Then, here's the procedure:
- Go to Start and type in "verifier" (without the quotes) and press Enter
- Select "Create custom settings (for code developers)" and click "Next"
- Select "Select individual settings from a full list" and click "Next"
- Select everything EXCEPT FOR "Low Resource Simulation" and click "Next"
- Select "Select driver names from a list" and click "Next"
Then select all drivers NOT provided by Microsoft and click "Next"
- Select "Finish" on the next page.

Reboot the system and wait for it to crash to the Blue Screen. Continue to use your system normally, and if you know what causes the crash, do that repeatedly. The objective here is to get the system to crash because Driver Verifier is stressing the drivers out. If it doesn't crash for you, then let it run for at least 36 hours of continuous operation (an estimate on my part).

If you can't get into Windows because it crashes too soon, try it in Safe Mode.
If you can't get into Safe Mode, try using System Restore from your installation DVD to set the system back to the previous restore point that you created.
Driver Verifier - Enable and Disable

Run verifer for 24 hours and then give us all the dump reports

This is the driver

Seems to be your virtual image equipment. Uninstall or update driver
PowerISO - Create, Burn, Mount, Edit, Compress, Encrypt, Split, Extract ISO file, ISO/BIN converter, Virtual Drive, DAA File

Offending driver
SCDEmu.SYS