Hey Brett - Welcome aboard.
Why not start by making your pages accomodate a desktop view:
Your 1280 width is already sprawling across ona & a half screens.
Try a 980 width for openers.
Second only to unwanted music, visitors hate a horizontal scrollbar.
Dreamweaver Version CS6 has it all set up for us. Check it out, even if you have to just try a trial.
Getting your site layout to respond to different viewport widths (responsive web design) requires some advanced layout techniques with Media Queries and multiple CSS styles for desktops/tablets/phones.