There’s very little effort on your part. You follow @FujifilmUS and tweet the answer to the following question: What movie should be redone in 3D? You’ll need to include the hashtags #3d and #sweepstakes to be in the running.
You don’t get extra points for creativity, so long, multi-part tweets about how movies filmed in 2D were filmed for 2D, so re-making them in 3D is a curious idea at best. Just say something like The Lion King and cross your fingers.
US-only, I’m afraid. Sorry. :(