Probably not to do with Firefox, maybe a bad driver or something to do with anti-virus or firewall.
Get this program. It will give you a good idea which driver is causing the crash -
http://majorgeeks.com/BlueScreenView_d6200.html
You need to setup Windows to save debugging info. Right click My Computer, choose properties. Then advanced, then choose startup and recovery 'settings.' Think you need to select 'small memory dump' or 'kernel memory dump' if not already selected.