This is the way. Win is already activated, no need to pirate anything. Just get a >= 8gb flash drive, download the installer creator app from Microsoft, and reinstall Windows. It will activate based on the licensing level the machine came with, minus the crapware, which is from the manufacturer’s OS image, not Microsoft’s.
Thanks! About 5 hours into a new playthrough of BL2 with my wife, so this is awesome!