If it ever happens, I think it'll go a little something like this:
1.) Ender will be an non-caucasian genius child from a remote, self-sustaining agricultural village, probably in Africa.
2.) After waterboarding half the African continent to locate Ender, the entirely-caucasian western military-industrial complex will kidnap him to battle school, incidentally murdering the remainder of the peaceful, unarmed villagers with depleted uranium and burning the village down with napalm in order to hide their acts.
3.) The Formics - who will never, ever, ever be referred to as "buggers" lest we think they're homosexuals - will closely resemble furry dolphins. Their peaceful intent to save us from global warming by teaching us how to satisfy our entire civilization's energy and industrial needs with nothing but bamboo and kudzu will be violently opposed by big coal, big oil, big steel, big labor, and big brother.
4.) Bonzo Madrid will be the blonde son of a prominent Klansman.
5.) The Battle Room will be the same as the Battle Room in the book, except things will explode, constantly, for no apparent reason. Fortunately, the kids will only be thrown onto their faces in slow-motion, and suffer no other physical harm.
6.) At the last minute, Ender will determine what's actually going on and try to warn the Formics about the MD Device. The Formics agree to surrender. Once they've disarmed their weapons, Hyrum Graff will destroy their planet anyway. And probably laugh.
7.) Scene disintegrates into vengeful students versus oppressive caucasian Battle School teachers. Ender kills Graff in violent, bloody, prolonged hand-to-hand combat. Mazer Rackham kills Petra. Final showdown, Ender has Rackham at his mercy but spares him. Ender turns around, Rackham draws a hidden gun from his boot, Bean leaps across Ender to take the shot and is mortally wounded. Ender snap-kicks Rackham down a huge air shaft and out an airlock.
8.) One year later. Earth is a paradise. Last remnants of Battle School staff have been chased into the depths of space, but they'll be back, repeatedly, for every sequel.
Comments and additions are invited.
UPDATE, Courtesy of Eduardo:
Ender will have a side-splitting, talking animal companion entirely rendered by CGI named Gar-Gar Blinx. He will provide most uproarious humor and comedic relief. He will talk silly, slip on things and fall down, and most importantly will have his own spin-off show on Nickelodeon with a complete line of action figures & accessories.