laptop not responding after 3/2018 Windows 10 updates

Absolutely not. To check, type 'Activation' in the Cortana search box and screen should say 'Windows is activated with a digital license ...', if you did free upgrade from 7 to 10.
Search box said "No results found for Activation."

If creating a new Local account fixed nothing, then we've verified a system issue vs user.
After install I clicked around checking things out, including Settings/Windows Update and seen that the very update I think caused the uproar was in the process of installing. I opened Google and added a few things, like my LastPass extension, so that I could use the browser as I normally would and see what happened. Suddenly Chrome froze just like it has been doing. I had to force a shutdown because everything was froze. After booting back up checked Windows Update again and seen that the install of that update had failed.

Note 3: Since many of your problems are typing and browser related, UNINSTALL this ...
This is a paid version and I do have all my product keys for all purchased programs on a list. I have stopped KeyScrambler from loading (and can now type in Edge). Would it still affect other things so that I need to completely UNINSTALL it? If so I'll be happy to do that.

I want to summarize a little here and then I will go and do the Safe Mode and Clean Boot ...
Before calling it quits in the wee hours, I had made Firefox my default browser (as I told dalchina) and worked in it for a good hour, as I have been doing this morning, with no problems so far.
(A note here ... My LastPass extension will not even load in Chrome anymore. Yet it works fine in Edge, IE and in Firefox.)
Everything on my computer is working and when I run into problems seems to be narrowed down to only when I open Chrome. My scheduled run of Macrium even opened and ran this morning, and when finished reported that it had been successful.

Having said this, I do have a big problem with my computer now and that is with booting up. And it doesn't act the same twice in a row; it's painfully slow. For instance:
I'll hear that startup music play in the background while on the screen it's still showing a bright blue window with "Please wait" and the little dotted circle is going round and round. Before all this started I never got "Please wait."
NORMAL: I have a choice to boot with Windows or Macrium. After I click Windows it immediately opens to that scenery screen where the box comes up and I can type in my password. After I do that my desktop opens within just a couple of seconds and when it opens all of my folders and files are on my desktop and taskbar icons are either in place or quickly pop up like ... bing, bing, bing.
NOW: It gives me a black screen for quite a spell before I get the sign-in screen. Then I have to wait again for a count before the password window appears so that I can sign in. After I sign in I get another black screen, usually for quite a spell, before my desktop appears and then when it finally does, none of my taskbar icons are there and it takes probably a full minute before they start appearing. Also, my desktop folders and files don't start showing up until after that.

Just so you know, C drive has 598 GB free of 681, so it's not because I am running out of room or anything like that.
I ran that Hard Disk Sentinel again this morning that dalchina recommended and it still gives me an excellent report.
I ran the Windows Memory Diagnostic and there were no problems.

Everything is working well right now. The response times are even starting to get back to normal as to how quickly things open and such. If Chrome is the culprit, how can a browser, that has been completely and newly installed, have this kind of effect on a computer?

"Search box said "No results found for Activation."
Click Action Center (lower R corner icon) then All settings\Updates & Security\Activation should get you this

"After install I clicked around checking things out, including Settings/Windows Update and seen that the very update I think caused the uproar was in the process of installing. "
If you were to do another Repair install, I would then pull the internet cable/turn off wireless, see if everything but browsers works. If it does, disable WU in Services so Updates won't download, then reconnect Internet and try browsers. If all is good, we know then that it's the March update. If not not, we know it's Chrome. Let's try this last.

I have stopped KeyScrambler from loading (and can now type in Edge). Would it still affect other things so that I need to completely UNINSTALL it? If so I'll be happy to do that.
No Q, since you have the keys, I would uninstall it completely to test. If you have REVO uninstaller, I go so far as to use it in Moderate mode to drill down to deleting registry items and AppData folders but worth quick test, at least to uninstall, in case it has processes auto-starting.

"Everything on my computer is working and when I run into problems seems to be narrowed down to only when I open Chrome."
I would uninstall it, and live w/o for a couple days for testing. Uninstalling will not remove your settings or bookmarks which will be restored when you re-install. Again, we're trying to narrow your problems down, one by one.
"while on the screen it's still showing a bright blue window with "Please wait" and the little dotted circle is going round and round."
I shut down at night. This is normal and exactly what mine does briefly, then log-in screen appears.

"NOW: It gives me a black screen for quite a spell before I get the sign-in screen. Then I have to wait again for a count before the password window appears so that I can sign in. "
This is a sign that startup is trying to load your video driver. Two things you can try. Turn off Fast startup by hitting Win(key)+X, open Command Prompt/PowerShell (admin) then type powercfg -h off then Enter. This will disable hibernation, Fast startup and clear the hibersys file. You will only have Sleep or Shut Down as turn off options. Few people even use hibernation but if you do, leave it off for testing.
Next, see if your drivers are up to date. Win+X\Device Manager. Go to Display adapters, expand, r-click\Update driver\select let Windows search. If this updates, will require a restart.

"Everything is working well right now. The response times are even starting to get back to normal as to how quickly things open and such. If Chrome is the culprit, how can a browser, that has been completely and newly installed, have this kind of effect on a computer? "
Have you looked at Event Viewer to see what is logged. Post a screener and another of what items are auto Starting. Open Task manager\Startup tab\sort by Enabled and let's look, eg;

This Google forum post is dated but may be applicable as far as the hidden AppData folder goes, since this is where your bookmarks and extensions are restored from. It may need a complete cleaning, if corrupted, as suggested (or use REVO uninstaller). This fix would require rebuilding all your extensions and you should export your bookmarks to a file so you can restore. - https://productforums.google.com/for...me/dUyZhUCWWtA

I haven't even read the above yet because I need immediate help. I'm at the screen where I select which Safe Mode option I want. How do I select it? I've tried the number keys at the side, across the top and I've tried the arrow keys. I get nothing.

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I just read through your last post. Lots of good information I've received from you and dalchina. I can't hope to repay you but know that I appreciate and treasure the responses of you both. This is some good information you gave me, but I have to get off this screen I'm on right now before I can proceed with anything. I'm typing this from my old desktop, that just keeps on ticking.

"I'm at the screen where I select which Safe Mode option I want."

You want Safe Mode with Networking if you want to test browser. How did you get there, from the Update & Security\Recovery, by hitting Shift+Restart on sign-in screen or msconfig menu ? Are you here? Then press 5 or F5 -

If you can post picture, if otherwise, would help too.

Safe Mode: I got there by hitting Shift+Restart on sign-in screen. I did use the number keys; both those running across the top of the keyboard and those on the right side. Nothing. Not even a flicker. And I also tried the arrows. I could not even exit by hitting the 'enter' key. I had to use the power button to get out of there.

Repair Startup: I used this and it said 'Repair Start Up could not repair your PC.'

Startup: I timed it this last time. It took a full 7 minutes from the time I pressed the power button to the time I was able to do anything on my desktop.

Chrome: For right now I am going to uninstall Chrome and let that go for a while because Firefox is working very well for me.

Start Up/Event Viewer: How do you sort Start Up by enabled? What is it that you want me to copy from Event Viewer?

Display Adapter: About this, when Win 10 was installed it changed the display adapter I originally had with this machine to Intel(R) HD Graphics 4000. I am now going to follow your instructions on this and see what happens.
RESULT: Windows determined the driver installed is the best driver for this system.

"Start Up/Event Viewer: How do you sort Start Up by enabled?
see my screen shot. Just click 'Status' at top. Take a screenshot of all 'Enabled' processes.

What is it that you want me to copy from Event Viewer?"
dachina posted this way back in post 2. But before you do that, I see that you posted hardware test results but not for a scannow, unless I missed it.
Seeing as how your RE may be corrupt, maybe you should do that first.

run from command prompt (admin): sfc /scannow
It will find and attempt to repair any file corruption (may appear hung on progress %, but just let it run). If scannow can't repair corrupt files, then run from command prompt (admin):
C:\Windows\system32>Dism /Online /Cleanup-Image /RestoreHealth

If that doesn't work, we have your ISO to repair from but let's cross that bridge later. Worse comes to worse and you want to bite the bullet on a clean install, 'dachina' is the Forum Guru when it comes to that process.