pentimentosound
The ASROCK Preparing Repair screen then a blue screen titled Automatic Repair with RESTART and Advanced options
Restart doesn't do anything and Advanced Options which shows 4
Continue (Exit and continue to Windows 10)    Nothing happens with that one
Use a device - with Hard Drive USB                           "            "
UEFI (FQT) SanDisk                                        nothing much happens there
 Trouble Shoot leads to 6 options see pic

I think you are gone into TROUBLESHOOT settings there?

Can you go back by one screen .. there you might have an option / icon for USE A DEVICE .. like this??

abacab

pentimentosound
Is my DVD drive likely to be plugged in properly if it's light works and it opens/closes and spins?

Well it has power! 
 
However, that still does not tell us if it is connected to a SATA port or that the BIOS can see it.
 
Have you physically verified the SATA connection?

 
So maybe the next thing to check in the BIOS is the SATA port connections. See page 65 in the manual.

I have tried all those to get the DVD drive "available and use the Linux disc as per abacab's suggestion.
I'll go through the SATA physically and then the BIOS
 
 
I did unplug my other 2 HDDs and there are only 2 things plugged into to SATA. The C drive and ??   would that be the DVD drive?
 
I may not be back on this evening, but thank you all!
Michael

I have tried to get to the DVD drive through "use a device" and to try starting from the Recovery thumb drive too

pentimentosound
I have tried to get to the DVD drive through "use a device" and to try starting from the Recovery thumb drive too

Well the thing here is that if the BIOS ain't seeing the DVD drive, neither can the recovery environment, or Windows...
 
The basic job the BIOS has is to identify all the hardware available to the system, then hand it off to the OS.  If the BIOS cannot see something, the OS has no chance of seeing it.
 
So first things first, the BIOS has to establish what hardware is available, then hand it over to the OS.

Makes complete sense....

SO...   after all that and a couple hours of Restore to the Acronis image I had, it's back to "normal". That image was dated July 24, 2017.
 
1. I'd unplugged my DVD drive not knowing it was SATA 2 and unplugged my E drive (Cake projects).... oops. That explains a lot. LOL   Have I got that right? C drive is SATA 0 and my DVD drive (D) is SATA 1?
2. 179 plugs are missing ..... so that will have to get dealt with    
BUT
What would be the best thing to do next? I do have these discs - Linux, Comodo and Windows.
I ran a Norton scan of the C and E drives last night though I wasn't connected to the internet.
I'm not sure I ought to connect it to the internet! LOL
 
I really appreciate all the help, encouragement and you all sharing your knowledge and expertise!
 
I suppose this is pretty good, but it still seems like there's more diagnosing to do.
How would you proceed from here?
Michael

From a Windows perspective, you just went back in time to a snapshot of your system as it was on July 24, 2017.  So your C: drive will be missing anything you added since July.  Going forward you may want to consider taking a new full image at least monthly. 
 
So now you have some catching up to do.  First things first, update your AV to the latest version, and get all the updates.  Then crank up Windows update and let it catch up.  Probably start that before bedtime and let it run.
 
Update all your existing applications and plugins, and re-install anything you acquired since July 24th.
 
Next copy your recent documents and projects, anything that you normally store on the C: drive, from your file backups - - you did have that all backed up on your other drives, right?
 
As far as hardware diagnostics, I'll dig up a few links for utility programs you can run to check you system health.  But since you got this far, at least it doesn't seem to be a complete hardware failure.  Maybe your drive is going bad, and that messed with your boot partition, so I will get you some hard drive diagnostics to run.

These two freebies are my go-to utilities for disk health.  Since they are not vendor specific, they will provide SMART health and other stats about all your connected drives.
 
CrystalDiskInfo  (just look for the blue 'Good' icons for each drive)
https://crystalmark.info/en/software/crystaldiskinfo/
 
PassMark DiskCheckup (just look for the green 'OK' on the Device info > Status for each drive)
https://www.passmark.com/products/diskcheckup.htm
 
PassMark DiskCheckup has a tab for Disk Self test.  It's probably worth checking that out.
 
Either of these utilities will easily identify the vendor an model of your drives.  You may want to go to the HDD vendor website and download their proprietary diagnostic utility, as it may offer more comprehensive diagnostics for your model drive.  Defintely do this if you see anything suspicious with the two programs above!

PassMark also offers a couple of other handy free utilities.
 
MemTest86 is probably the most well known.  You can install it on a USB stick and boot your PC standalone, let the memory test run on your RAM overnight with multiple passes, to ensure you are not having memory errors.
 
Bad disk drives and/or RAM errors can lead to data corruption, so it would be best to rule them out.  Remember, you should always see '0' errors on a RAM test.  Any errors means a failed module.
 
https://www.memtest86.com/
 
They also have a cool PC benchmarking program that tests your hardware performance wise.  Not really a diagnostic tool, but it can show how well your PC compares to other systems.  And it does exercise your PC a bit, so if it runs to completion, your PC may be OK. 
 
PassMark PerformanceTest
https://www.passmark.com/products/pt.htm