[Lynne]

In order to comment out html (which are what templates use), you use the following lines:

<!--
all the stuff to comment out
-->

However, that will still show in your source code. I would comment it out at first and see if the page works how you want, then I would go and delete it. Or, save the current navbar template, delete the stuff, if it doesn't work then go back to a saved copy of the navbar.

As an aside, if you are wanting to comment out php (which are what plugins and php pages use), you would use:
/*
stuff to comment out
*/