Centering Entire Flash Site

Hello all! I am planning on making a site entirely in flash. I only have the intro movie done so far, but have a few problems that I know I am going to run into soon:
First: When the movie is played in internet explorer, it full-screens intself. It still looks decent, but not as sharp as the regular 550x400 that I built it at. What I want is a way in which I can set this video that it stays at this size in the top center of the browser window without resizing, and doing this entirely in flash…
Second: How do I do the same thing for the page, but so it automatically resizes to fit the viewers browser best, such as done on this site: http://www.ya3.has.it
Third: How do I create a menu like at the site http://www.johnmayer.com or the one in the link above at ya3.has.it. I know you wouldnt have the space nor desire to write it out for me, so know any place that may have a tutorial on a menu similar to either of those? I wasn’t a big fan of the results of the one here on kirupa.
Thanks a ton for the time to reply here guys!