Hard disk failure. Had to get a new PC. HP Pavilion, 12 GB, 1TB with 120 SSD. WIndows 10. No idea how to transfer stuff over from the dead drive and if it's worth forking over the money.
However, if it was the hard drive controller on the motherboard that failed, it'd be pretty simple to just take the old harddrive out of the old PC and plug it into the new one. It'd show up as another drive in the list of drives you already have, and then you could just browse to the files on it.