abacab: thanks again so much, yes I go into the BIOS via F2 at startup (F2 and F12 are my only options, F12 is supposed to take me into one time boot according to the manual but it doesn't) and my only options for Boot Option Priorities in F2, the BIOS are:
Boot Option #1 Windows Boot Manager
Boot Option #2 Onboard NIC IPV4
Boot Option #3 Onboard NIC IPV6
I've tried all three with the DVD Macrium Rescue Disk inserted and they all bring me immediately right back into windows.
I don't know what NIC IPV4 & 6 are, but they have a DVD and Flash drive icon next to them in Advanced Startup in windows (a link under Settings). If I go in thru this link (as opposed to the BIOS), I get the same options as above and they all restart immediately back into windows.
Incidentally, my total time online during this week of activity is about 15 minutes. Enough time for Microsoft to demand I download the updates (1803). Yesterday I got a BSOD upon startup after leaving sleep mode so I am not in a good position now.
I sincerely appreciate your and everyone's help but I am not sure I can crack this cookie open and I may have hosed my pc (essentially brand new, barely used, maybe 40 hours) by trying to create a rescue disk and allowing Microsoft in the backdoor.
Your help has been a super help over the years, you are a great guy!