Dark Forces
Basically my first FPS experience as a kid. I was terrible at the game, but with a lot of time and perseverance, I got to the end. The first time you run into a Dark Trooper, I think I shit my pants.
Just getting that game to run on my shitty Packard Bell was a WOW moment for me.
My autistic quest to get that game to run on my piece of shit PC is actually the main reason I know how to IT like a fucking pro today.
"Well, guess I'll read the DOS manual and these reams of print-out FAQs about memory management, boot disks and drivers, go to CompUSA and spend 200 dollars on more RAM and start shoving things into my computer..."
WOW. Nevermind the fact that it takes 8 minutes to load a level, this game is fucking rad.
Beyond that. Onyxia going airborne was definitely a WOW moment, and Ragnaros popping up out of the lava. My actual first WOW moment in WoW was realizing in beta just how fucking big BRD was.
Big world in SMB3 and the airship parts in the last world were WOW moments. The jump to Super Mario World over the original NES was a WOW moment.
Beating Culex in Super Mario RPG and Kefka succeeding in blowing up the world in FF6 was a big WOW surprise. Chronotrigger had too many WOW moments to mention so just that whole game honestly.
The game that WOWed me the most on graphics for its day was actually Max Payne. I built a computer for someone at work to run the game and I was pretty floored, that game was way ahead of its time graphically I thought.
As for Ut's post, this is actually the moment that punched me in the gut in Bioshock: Infinite:
But that first conversation with Sovereign is definitely my favorite story moment in a video game. Algalon's speech in WoW was pretty well up there too.