Windows 8 not accepting password

I was asked to de-clutter a Packard Bell laptop which was full of photos and downloads. I deleted any of these that were not wanted and uninstalled some superfluous software. All was OK for a few days and then it stopped accepting the login password, although it had accepted it many time previously, it keeps asking for the last password used. Additionally it does not respond to key strokes nor will it run a boot disk. It just sits there waiting for something. Is there a master password?

On the asssumption that I might be able to find the hidden restore partition and and use the restore facility after I had transferred all data files for safe keeping. I removed the hard drive and put it in an enclosure, then connected it to and restarted my Desktop PC, it immediately tried to take that over and I had to power it down to stop it. I then found a backup IMG file had vanished from the PC.

At this stage i don't want to get a new HD and I would be very grateful if someone can guide me out of this problem