Turn off pc while updating
The only reason it tells you not to shutdown is that the updates are important (...Microsoft).
If the LED turns on or off in response, your system is still alive somehow. If the CAPS LOCK key does switch the LED, then look at the HD light on your system - if it's blinking them it's defintely doing something and you should give it more time.One hour is quite unusual unless your system is really, really slow.If CAPS LOCK works but your HD light is remaining off, give it about 5 minutes and restart it. In all probability your installation is damaged irreparably. (chkdsk - which can be run from a bootable medium).
At this point I'll ask if you have yet realised how invaluable disk imaging is. This is the sort of scenario where this is so valuable.
Then check your system's Event viewer for clues on what went wrong.