4) Last Order: FFVII (Animated feature, 2004 - days(?) before FFVII)
Available in the US only on the Advent Children Collector’s Edition DVD, this animated feature is an OVA (original video animation) meant to act as a prequel to VII and a companion to Crisis Core. Narrated by Tseng the Turk, the story goes back and forth between two flashbacks of things that happen during Crisis Core and are referenced in VII. The first takes place five years before VII starts, when Sephiroth goes nuts and trashes the town of Nibelheim. Sephiroth also kills Tifa Lockhart’s father (as if we need another reason to hate him) and Zack and Cloud are there too. The second flashback occurs just before VII starts, and features Cloud and Zack fleeing Shinra.

If you can’t be bothered to play Crisis Core (what’s wrong with you?), then this is your best shot for filling in the (huge) plot holes of FFVII.

5) Final Fantasy VII (PSOne, 1997 - Current)
We all know what happens - rock falls, everybody dies.

6) On the Way to Smile (Novella, 2005 - 1 year after FFVII) 
Okay, so not everybody dies. This literary gem is supposed to preemptively fill in plot holes for Advent Children as well as tie up any loose ends left over from VII. The novella appeared in the pages of V-Jump magazine and on the official Japanese website for Advent Children in 2005. It’s made up of three side-stories told by Denzel (the orphan boy featured in Advent Children), Tifa and Barret that sort of tell a “where are they now” story for the surviving FFVII characters. It also explains how the Lifestream saves Midgar after Sephiroth's meteor falls.

So if you can read Japanese or find a good translation, or plan on buying the Advent Children art book, you’ll have a much better idea of what the hell is going on in Advent Children than if you just watched it cold, like most Americans.

7) Final Fantasy VII: Advent Children (Animated feature, 2005 - 2 years after FFVII)
Let’s not mince words: this is a CGI acid trip. Forget the plot - it’s just a lot of Cloud angsting about Aerith being dead, Tifa angsting about Cloud missing Aerith, and some stuff about mako baptism. Sephiroth is somehow back from the dead and… yeah, stuff blows up. It’s pretty:

8) Reminiscence of Final Fantasy VII (Story digest, 2005 - 3 years after FFVII)
Reminiscence is technically an animated feature because it’s made up of clips from the original Final Fantasy VII and some shots of locations from Advent Children. It's basically a highlights of FFVII piece instead of a stand alone plot supplement. You can watch all three parts by clicking the links below:

Part I
Part II
Part III