I'm afraid I can't help as much with the search engine placement but I know more about the technical aspects of sites. The main thing I notice is the stray text above the image table in the main part of the page. The text is black on black so it only shows up if you highlight it. It's actually part of a tag for your forum button. If you go into the source and find the text that says 'onmouseout="button_off('guestbook'); return true" onmouseover="button_on('guestbook'); return true">' and move it into your image tag for the forum button (<img src="images/guestbook_off.gif" ...) that should fix it.
I apologize if I've told you anything you already know.