I have downloaded Napster and got the files for myself. The “Helicopter Scene” or “Theme of Sonic” is just the background music went Sonic jumps out of the helicopter.
“R.U.N.” is just of the E3 2000 promo background music, which is at the same quality when it was first put out on the net.
The intro or Sonic Adventure 2 – The Beginning music is just the Press Start seen on the SA2 demo.
We already know about City Escape and the Truck theme. I have seen two other so called versions of the City Escape theme, but they turned out to be the same thing.
“Sonic Adventure 2 Remix” is fan made and in IMO, not that great of a song.
The song about Shadow (I have seen it with many different names) sounds like it might be from SA2. It has no words to it and sounds more like a fight song. From the tag, it’s by Hideki Okugawa and the name of Shadow’s theme song (like Sonic’s is It Doesn’t Matter) Shadow’s is “Warrior’s Shadow.”
Plus there are several Napster users who have these songs now.