Integration of Wordpress into HTML/CSS template

Hi 1. I have two HTML/CSS pages - one homepage, one internal page. You can see the homepage at www.identifiedinvestments.com. (The internal page will be finished shortly and I will provide the HTML/CSS) I want to integrate Wordpress with these pages, i.e. make it a Wordpress-powered site. 2. The homepage has a dynamic dropdown menu showing various links. These links will need to be populated with the Wordpress "categories", "subcategories" and/or pages. The internal page will also require this menu. 3. We will also need two jQuery effects, (i) a slideshow/gallery, (ii) a way to change the background image of the site (using [login to view URL])