I have the same problem with my HP Envy laptop. After windows update and reboot, the screen is black with just the mouse cursor. I can control-alt-delete and bring up menus to reboot.
After going into the recovery screen on reboot, I can restore to a previous version of Windows. The problem is that the windows update keeps happening and this issue persists. This is very annoying. There needs to be a permanent fix for this.
In the meanwhile, I keep creating multiple restore points in fear of not being able to recover.