Heh, while reading your text I thought "Lux Aeterna is one of the more "epic" sounding soundtrack songs..."
That's what's playing in your video. There are quite a few other sweeping scores in film, though.
I find Returns a King from 300 to have a pretty epic feeling, in terms of scope. Almost anything with a chorus, really.
Like Carl Orff's O Fortuna:
Terrible movie, but Summon the Worms from the Children of Dune soundtrack has a good, epic feel:
Anything by Alan Silvestri
And some non-score, epic music that gets me in the mood to game/party/get pumped up:
(Yeah, I know, the song lyrics are really about a pussy, but, eh...)
Bodies, from Drowning Pool:
(Bonus: Deadpool video!)
There are a few more that are sort of floating around, but I can't remember titles/artists. I'll scan around my music collection and see if I can jog something.