I'm trying to export an ID (CS 6) file to epub. I'd like to have the different parts of the front matter (praise for the author's previous book, title page, copyright page, etc.) start on separate pages, which I can do by editing the first paragraph style on each of these pages under export tagging. But I don't want a separate entry for each page to show up in the nav toc. I only want the chapter titles to appear in the nav toc.
The Nav TOC is created by creating a TOC Style under the Layout menu. Only the paragraph styles you choose to include are used. When you export, select that TOC Style in the export dialog. So you should only include Chapter Titles here.
So if you create a choose paragraph styles in the front matter which aren't used in the TOC Style, they won't be included in the nav TOC.
However, you can still use paragraph styles that create page breaks. Those are set the the Paragraph Styles menu under Edit All Export Tags.