The antivirus you are currently using is known and contributing to your BSOD crashes, consider uninstalling it with the Norton Removal Tool and replace with Microsoft Security Essentials at least to test. If we know that it wasn't the cause of your problem you can always install it back.
Recommended antivirus program for Windows 7 based on stability compared to others:-
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.
Free up your start-up, keep nothing except the antivirus:
Run the System File Checker that scans the of all protected Windows 7
system files and replaces incorrect corrupted, changed/modified, or damaged versions with the correct versions if possible:
Run Disk Check on your hard disk for file system errors and bad sectors on it:
Let us know the results and further BSODs if any.