There is something wrong with your chipset HDD errors (?) / graphicscard drivers / motherboard drivers can be anything.. I had this similar issue before with a friend. I told him simply to reinstall the entire windows and it worked suddenly.
What I can't explain is why the WoW crashes. It may be something related to the chipset or your RAM..
Not sure either. WoW never crashes in LFR's, raids or anything else - only when I start up HB and the rotations begin, then they both shut down at the same time after about 5-8 mins. I noticed several other people experiencing the same issue since this new release but we never experienced it with prior releases. I'll will probably do a bare-metal restore anyways just to test that side of it.