Fixed it - Just got off the phone with AppleCare
I am glad I stopped where I was last night and didn't do anymore damage. I knew I was in a precarious situation when the newly created Mail folder in my Library had different contents than my Mail folder I'd drug to my desktop from the Library.
Here's what the tech said I did wrong in following the less than adequate instructions from the AppleBlog link in my previous post; inadequate because it didn't say where to move the folders and plist to. I was advised that I needed to QUIT Mail before dragging ONLY the Library>Preferences>com.apple.mail.plist file to my desktop. The other two folders need to stay in the Library.
After you are out of Mail, on the desktop click on the plist to highlight it. Use Control-click to display the popup menu and select Copy for the plist. Open finder window with ONLY Preferences (~Library>Preferences) highlighted. Go to the Finder>Edit>Paste drop down menu of the toolbar. It will ask if you want to replace the newly created plist with the one you just copied. Select replace. Relaunch Mail and that should restore all your Mail Profiles and retrieve your messages.
This process even brought back my mail folders and put all my saved messages back where they were filed. I didn't have to get into my archived messages file after all.
I did have to rebuild my ISP email profile because it got wiped out in my haste last night. Make sure you know your email passwords in case you end up rebuilding your accounts. Luckily, it restored all the rest of the information as soon as I put in my password. It's even working to let me send from that account for the first time in months.
YIPPEE! I'm using Leopard, iWork 9 and iLife 9!