A 3d dvd is no different than a normal dvd except they require special players and special glasses to view the 3d format. http://entertainment.howstuffworks.com/digital-3d.htm
Yes - but, of course, they won't play in 3D
No. All current 3D disc content is HD and so use Bluray discs. You have to have a 3D Bluray player.
Yes
Is any blu-ray movie could be played on a blu- ray player which is not 3d/
Beacaus bluray is newer and they think everybody has a bluray player... eventually it will come on dvd.
SOME of the 3d dvd have menu option to watch 2d or 3d and some have a menu to maximize the performance of your 3d experience but some have nothing
It is highly unlikely that Final Destination will be in 3D this is because the technology is simply not there yet. Sony have just this week announced plans a 3D DVD player. It should be out on the 5th January 2010 and it most likely will be in 3D because they will provide 3D glasses like they do with (for example) My Bloody Valentine 3D x
Yes
Never Say Never is on DVD but it isn't in 3D
No. Blu-Ray discs will NOT work on DVD players
No