There are a couple of possiblities. In this case, you said it was switching to a networked video file. Was the module listed that the fault occurred in (you can find that by changing your system settings to halt on stops in the System Properties Recovery section - that will stop on the blue screen and you will need to use the power button/reset to restart it.) My first guess (and it is a guess) would be a NIC driver. My second would be a file system driver such as a RAID controller addin or custom USB or Firewire driver.
Without sending use the dmp files, set the system to halt on errors so that you can see the first page of the STOP error.