Expression Engine website tweaks and slight redesign

Hi -- after being abandoned by a developer just before finishing a website redesign, I'd like some Expression Engine help clearing up a couple of things. Specifically, I have a new-look front page that I need to switch with the currently live one and a completely new landing page that I'd like to place at the root of the domain. I.E. landing page at [login to view URL] and front page at [login to view URL] or suchlike. Both the new front page and the landing page are more or less finished. It's essential that internal URL syntax is retained for the sake of Google PageRank, of course. Also, if you're a decent designer too, I have some small changes to the new design I'd like to talk about, although this is very much secondary to the first part of the task. Many thanks....