Well after a few hours, I've got it mostly working. Lots of registry cleaning and many reboots.
Interesting security mess. Not 100% certain of it all, but it looks seriously ugly and dangerous.
Problem has to do with where I installed the update from apparently. I live in dial-up hell. So I took the machine to a friends place that has FIOS, and updated it from there. The only thing my computer ever knew was the router password. I've been to this friends house before with this computer, and never had any problems.
Now, at my home, it's showing on my friends computer and my friends Onedrive on my PC. Whoa! This is seriously not good!
At no time did I ever log into my friends computer, her Onedrive account, or give Microsoft her account name or password. Seems like Microsoft automatically granted me access to her account simply because I was on her internet router.
Seriously disappointed with the "improved" start button and the starting up of installed programs. Non functional left click. Nothing happens when I left click. Right click and there it is. NOT! It's taken you to the Remove Programs section of the Control Panel. You click that program icon thinking you're going to fire it up and instead it delete it. Lovely.
Trying to find where programs are living is remarkably obscure. Once I found it, it's about 5 extra clicks to access them compared to Windows 8 or 8.1. Maybe there's a better way, or an upgrade coming. But right now, this is nasty. Swipe in from the right, select Tablet view, a few other steps that I can't recall, and then I get a skinny list of programs on the left of my screen.
One other very obnoxious gripe. They've apparently taken away the spinning circle that tells you that you're loading a program. Not always, but most of the time. Click or double click an icon, and nothing happens. But a few minutes later, with no warning or indication, and the program pops up.
Touch screen is still only semi functional.
MS Office is now functional, but awkwardly. It now wants me to reverify my users licence every time I access any Office program. Doesn't matter whether I select yes or no, it fails to verify but does fire off.
Weirdly right clicking anywhere on the desktop screen brings up an "open MS Word document" option. Which if you select it causes a fake document to drop on the desktop. Fake because it actually doesn't open Word, and fake because if you attempt to open the document it cannnot be opened with Word.
Can't say that I'm impressed with Windows 10 so far. So far I haven't seen anything that makes me think it really is better than 8.1.