A few quick words of advice:
Can anybody give me an option of how to get the background image to go down through the navbar div? I supposed I could try moving the navbar div out of main, but I'm not the CSS guru, so I'd be afraid of messing the whole page up. The other option would be to cut down the div so it fits in the navbar div, I suppose.
I can't go right now into the full details of your situation, but my advice is always to find an existing and finished Drupal theme and then customize that until it looks as you need. You will find that way that many elements (like Drupal tabs etc.) are already setup for you. Probably will prove to be less work in the long run.
On the same page, I also need to replace the text for each primary links with a button image and mouseover image. I've seen a few options for ways to do that. Does anybody have experience doing this, and suggestions of what way would be the easiest?
Find the right menu theme functions and over ride them in template.php
HTH, Fred