Computer blue screens when running a LAN game

I have been trying to host a LAN game to play with a family member in my household. Twice now, shortly after setting the game to LAN mode, the computer would suddenly blue screen. It would then automatically restart before I could get the time to read over what the blue screen error says.

We are playing on an older world which 1.9 would not initially recognize for some odd reason, until I tried opening, saving, then closing it in mcedit.

The blue screen occurred around the time I would look at/approach the doors exiting my friend's castle.