As far as I'm aware they won't as most 3d movies I've seen are on blue ray which 360 ain't got, unless you might have downloaded a 3d movie in the right format. Then the xbox might pick it up on a portable usb or hdd, sure most 3d films are done in mkv, so try the optional media update for it and give it a shot you never know might just work. As for the 3d xbox games they just work via the hdmi cable like black ops for example. Hope this helps in some way m8
