At Admin Panel -> Settings -> Switches you have a "forum jump selector menu" option. When this is enabled, you'll find toward the bottom of every front-end page a dropdown selector topic your site's forums which will take you to the selected forum if you select it and press go. This can help people navigate your site more easily.

To change the number of levels of forums displayed in the jump selector, go to Admin -> Forums -> Forum Settings. Make sure not to have an extreme number of forums in the jump selector -- it could slow down your site significantly if there's that much extra text to process, both in terms of server side generation time and client side load time for slow connections... plus a list of 1000 forums is impossible for a human to sort through to make a selection. In most cases, just the top one or two levels of forums should be displayed.