That's interesting, Gabriel. I don't know whether or not Safari was trying to "open all saved bookmarks", but the suggestion sounds reasonable. Good luck with that... I don't even guess how many tens of thousands of bookmarks I've saved over the years. I almost "freeze up" just trying to imagine. Surely I no longer need them all, but having been a developer for several decades, I frequently use a good many of them, finding it much quicker and easier it is to search within my [well-organized] bookmarks, prior to Googling for new references to any given topic. That's to say little of the immense time investment that would be required to sort through and slim down my immense collection of bookmarks.
GOOD NEWS THAT MAY HELP OTHERS WITH THIS ISSUE...
As I mentioned in my initial post, it took me over 14 hours to do the original emergency security update from macOS 12.1 to 12.2. This unreasonable time allotment was do to numerous crashes during the update(s), causing me to start the download(s) all over again from scratch. As I indicated, I was able to reinstall Monterey 12.2 using the Public Library's, faster and more secure WiFi. Although I repeated got the message that the update would take 5-1/2 hours, it actually completed in about 2 hrs.
Since the reinstall, Safari now froze up within seconds... no longer allowing me to load ANY pages. It did so, while attempting to load tabs and/or windows that had previously been opened. To resolve the issue, I would force quit Safari, then upon reopening it, I immediately closed the front browser window as quickly as I could. Typically, it would then freeze again. I continued this process until all tabs/windows were closed. I then opened a new private browser window. This seems to have stopped the crashes. And (knock on wood) I have not experienced any more freezes... yet. It's a bit early to make a final judgement, however.
Hopefully, this information will help others who have also been experiencing Safari lockups. I have no problem with the concept of using "private browser windows". But I have to wonder why one can now ONLY use Safari within a private window. This was never an issue for me prior to the 12.2 update and I'm confident that the update was indeed the cause of the issue.
I do hope this information helps others with the same problem. And I would love to hear feedback from anyone else who did have similar experiences.