You did a good job, I got the report that I needed
There was only one mini dump report (shows you had one BSOD).
It is impossible to get a definitive answer based on one report, but I did get clues, so lets start there.
Ataport.sys was mentioned as a potential cause as was Security Essentials. May I suggest
Run a full antivirus scan
Download, update and run a full scan with malwarebytes
Run an SFC Scan
If nothing else seems to work
Uninstall Security Essentials and replace with another Anti Virus
Before uninstallin Security Essentials, make a System Restore point, so you can go back if that is not the cause. System Files - SFC Command avast! Free Antivirus - Download Software for Virus Protection