Verified answer

well... you don't really have much choise here :)

Actually there are two FF's that have being filmed -

this one came first: Final Fantasy: The Spirits Within (2001)

Advent Children (2005) is totally different from it (storyline, guys playing in and so on), so both aren't conected in any way (except for the fact they both are Final Fantasy games).

Now, tricky thing is you need to get familliar with the storyline of Advent Children before you see the movie, in order to understand it completely (i didn't do it, so it took me some 4-5 times of replaying it to get the story).

I mean, you need to read something about the game FFVII (that's Advent Children), because the movie is based on what happens AFTER the game story.

And .. that's it...

anything else you saw in youtube or where-soever is trailers for other parts of Final Fantasy (the game). Like there are some for FFIX and FFXII (I think), but they've never been filmed... which is such a shame.

anyway. hope that'll light your way.. in a way :)

They aren't connected, so it doesn't matter. Advent Children is MUCH better.