The music that starts at 2:40 in this video. I must know what it is
and where it's from!

http://video.google.com/videoplay?docid=4308386183977184660&q=warcraft+dragon

sounds like generic 'let's raise the tension' background elevator
music and not any real composition but i could be mistaken

raise the tension? if it sounds to you like something that was done
impromptu, you should be writing music. no, it's not generic music.
there's an origin and a name to the music. believe me. it wasn't
created just to make this video more appealing. the top gun theme that
comes after it is far less impressive, in my opinion. and you wouldn't
think of that was just generic background music. would you? it's just
offensive to the composer, that's all.

It sounds very much like a John Williams composition...hmmm I can't
put my finger on it

THE ANSWER IS...

It's from The 13th Warrior movie soundtrack, by Jerry Goldsmith.  More
specifically, it's an edit of the finale "Viking Victory" track.

I know a few other answers of this variety.

WOW! You're amazing! Thank you!!! I'm going to rent the movie to see
where and how they use it. If you could tell me when they use it, that
would be nice...

Do you know the name of the music that comes before this? It's by Paul
Oakenfold, Zoo York, Winter Chill...but I can't find the name of the
specific piece. I'm only finding it with different instruments (much
less intense version).