Suzanne's help in solving this problem, along with her tips for Booklet
Printing with earlier versions of Word, have been of great value in my
present project.  With regard to the pagination issue, the tips on "How to
set up a document with front matter numbered separately" address my issue
only partway, as it seems the page numbering can be turned off completely for
only the first page of a Section, and I needed it off for all Section I
pages.  Moreover, additional characters placed in the footer in any section
(an em dash before and after the page number) pop up in all sections.

However, I did come up with a Band-Aid® fix that works in my instance, and
it might come in handy for others.  To hide the page numbers on my several
Section I pages, I simply covered them with a white-filled, opaque rectangle
(no border) generated with Word's drawing utility.  Not elegant, but it
works; be sure that the Format/Auto Shape/Layout is set to place the
rectangle 'In front of text.'