1. Can I use Dreamweaver 8 to change up the layout?
I don't think so. The site layout is controlled by template files (sometimes multiple template files). They pull the styling from the CSS file.
3. How on earth can I add the logo to the site?
Go to Admin CP > Edit > Inserts. The logo at the top of the page is placed by the code in the "Header Insert". You can use html code to place the image in the top or use a skin variable code so the skin controls the image placed in the header.
Any information, so I can start changing up his site...
Yep, read read read. Read all the FBB Docs on this site. Read the built-in help files (behind the ? icons). Search this site for information. In most cases somebody else has already asked the question in the forums and the answer is documented.
And it is going to take a lot longer than 2 hours of reading. It could easily take days or weeks of working with FusionBB (and reading) before you really start understanding the software, especially when it comes to group permissions.