I have been trying to play it by laying my pointer finger across the 12th fret, and my ring finger or middle finger, over the two notes on the 14th fret, but whenever I do that the B and e notes on the 12th fret won't ring. That is the very first ascending/descending part.

Thanks for any help
You should probably sweep it. Look for lessons on sweeping / sweep picking on this site
You have to roll your index on the 12's. And you have to move your index up so the tip is on the B string after you play the G string.
It's called a sweep or an arpeggio by the way.

Here's a video that might help a little: http://www.vimeo.com/3869006
I wouldn't bar my indez for all 12 fret notes.

Fret first 12 fret note w/ index, then remove it, fret both 14 fret notes with a barred ring finger, then bar the next 2 12th fret notes with your index.

But don't let them all ring together, right after the note sounds lift your fretting finger ever so little and the note will mute out.

Thats just how I would play it....some would bare as much as they could.
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Wow you guys are awesome, thanks! I can't wait to get home and play now. I should post here more often, I think.