After more evidence of my son breaking into my tablet (darned 11-year-old... going to be a true Social Engineer hacker, if I can't get through his thick head that he'll lose all computer privileges...), I changed the password this morning... and can't remember it now.
Unfortunately, after multiple failed password attempts, IT IS NOT ASKING FOR MY GOOGLE LOGIN TO UNLOCK. I don't seem to be able to get to the "failsafe" unlock mechanism any more, and so am looking to do a complete factory reset.
I've seen instructions to hold down the Volume-Up + Power buttons to initiate this (remember, I can't log in, so I can't do this from settings.) All that happens is that the tablet goes into a mostly-blank screen showing what is probably a newly-opened box, and a blinking Android that says "Downloading...". I let it sit for close to two hours in this state, and nothing. It did respond to a power-down from here, but just came back up to the password login.
What am I doing wrong? (Apart from choosing such a simple password as 10 U/L/num characters... obviously not sufficiently complex...).