This part of the wizard is only seen when you process a file for printing. This option, intended exclusively for use with Word for Windows, produces a manual-style table of contents similar in format to the one shown on the dialog.
The table of contents uses the formatting styles of the output document itself as a guide to indents and subheadings. Naturally you can change these prior to printing if you would prefer a different appearance, but be careful not to modify the field references used by the table of contents entries when applying different formatting styles.
Like the indexing feature, the table of contents should update dynamically when you modify the document. To be on the safe side, save and reload your edited document prior to printing to insure proper page references.