Hrmm I thought the features page just about exactly answered your first 3 questions.
http://www.microsoft.com/windowsvist...s/default.mspx
Those pages gives you some screenshots of the new 3D interface and everything.
As for the 4th question the get ready link gives you a overview of the 5 different editions of the OS.
http://www.microsoft.com/windowsvist...s/default.mspx
If thats not quite what you wanted, this thread gives you a side by side comparison of features.
http://forums.microsoft.com/TechNet/...7581&SiteID=17
As for the new things you are looking for the see the possibilities link gives you short videos of the OS.
http://www.seewindowsvista.com/