YIKES! That was scary to read, but I'm glad to hear your system was able to recover.
This seems to be a singular occurrence, and I can't say for sure what may have caused it. The only thing I can think of would be the creation of the game's save file causing some sort of hiccup with other systems while the game is first initializing. I'll make a note of this and try moving the save file creation to sometime after the game has started to run. Hopefully that way, there will be less processing right at the start.
Thanks for taking the time to post your experience!
-Jack