Why? What do you think doing this will accomplish? Are you skilled enough to
avoid crippling your user's use of Word?

You can customize the menus in your document to remove these commands from
the menu when your document is open. No macros required. Tools > Customize.
Just make sure that the place to save changes is specified as being your
document, not normal.dot.

You can likewise create a macro that does nothing in your document and
assign Ctrl-S to it. Again, make sure you are making the changes in your
document, not in the template or in normal.dot.

What happens, though, if the person does make changes and clicks on the
close box?

Bottom line... Anything someone can see, can be copied/altered.