Using a service like youtube would be good for the video because now embedded youtube videos play in html 5 if flash is disabled on the device accessing the webpage, but it'd make it more complicated to have the site know when the video is done playing automatically.
I think it would be better to just have the video in the middle of a circle the main page surrounded by curved menu options or whatever and play, but that's just my opinion. Theoretically you should be able to set the menu div above the video so it looks like the video is contained inside a circle (which would probably make a really cool effect!)
Here's a quick mockup I did... something like this?
Appreciate the idea, but not sure it matches up with what direction the website would be going. I probably should of avoided using the word "video" and rather used "animation" because the intro animation would segue into the website layout, not be inside the layout itself. Though I suppose with "progress", new limitations are made because of dated tech. Also, your image isn't working.