I don't work on a Mac, but your problem suggests that the layout has been inadvertently changed in the template, although you also say that starting a new document opens properly. To me, this indicates that when you said "whenever I open Word," you are referring to existing documents, not starting by opening a new document to begin with. That would imply that you have inadvertently saved the change to one or more exisiting documents, and/or that a template beside the Normal template is attached to your existing documents. So, I think you need to open whatever template is attached to a document that opens in "Notebook" and make the change there.

I don't know what the "Notebook" layout referes to; it must be a Mac label. In any case, this probably falls in the View category of layout options.

Hope this helps.

Best,
Ulodesk