Seems my problem is similar to monica.favara's issue a few months ago. Hannah wrote to me and suggested I contact my hosting provider. Did that, and they said they will not just allow me to reinstall WP. Before I get anyone annoyed, let me be more specific with what exactly is happening.
I have made several product categories and they have items assigned to them. When I view the Product page, there is a drop down list box, "Select a Category" and all of my Categories appear there.
When I go to the Edit Menus screen, and look in the Categories section, under the "View All" tab, only 3 Categories are listed.
My goal is to be able to see the same list of categories in the Edit Menus screen as I see in the Products screen.