Thanks.
Please uninstall Norton. Norton tends to cause BSOD-s and often in the situation you describe. Please uninstall it the Norton Removal Tool and replace with Microsoft Security Essentials
at least to test. You may install it back if we know it wasn't the reason of the crash.
Microsoft Security Essentials.
Recommended from a strict BSOD perspective, compatibility & stability compared to other antiviruses/internet security software. It is free and lightweight:-

Do not start the free trial of Malware Bytes; remember to deselect that option when prompted.
Run a full scan with both (separately) once downloaded, installed and updated.
Perform a System File Check:
- Click on the

- Type CMD on Search
- Left click and Run as Administrator
- Type SFC /scannow
Full tutorial here:
Disk Check on your hard disk for file system errors and bad sectors on it:
Update the video card drivers:
Code:
Driver c:\windows\system32\drivers\nvlddmkm.sys (8.17.12.5896, 12.58 MB (13,187,176 bytes), 7/10/2010 6:38 AM)
METHOD:
Reduce items at start-up. Nothing except anti-virus is required:
POst back results.