[meteorite-list] Accretion Questions: Age & Material

[Meteorites USA]

I think I asked something about accretion and planet formation about a 
year or so ago onlist, and since then I've done a bit of study on it. I 
still have a few questions though. In the early formation of our solar 
system, the protoplanetary disk that fed and formed the planets, we know 
that material accreted over billions of years around the Sun, but some 
debris was left over.

If the asteroid belt is some of the "leftovers" from the formation of 
our solar system, and most meteorites come from the asteroid belt 
between Mars and Jupiter, then what of the Kuiper Belt?

Could the Kuiper Belt material be even older than recent studies have 
determined Northwest Africa 2364 to be since NWA 2364 most probably came 
from the Asteroid belt?

Are there any known meteorites that come from anywhere further than the 
asteroid belt? Could they? or would they be swallowed up by Jupiter 
before reaching the asteroid belt?

This brings up another question about star systems which are very close 
to one another. What are the chances of material passing between them? 
We know the massive forces of the stars gravity holds the protoplanetary 
disk in place but what about the debris on the furthest outer edges of 
the disk? Would the orbiting/spinning of this debris cause them to be 
flung out into deep space away from their parent stars toward other star 
systems? Is this where comets come from? or the Oort Cloud which 
surrounds our entire solar system?

And this brings me to my final question, though not really directly 
related to accretion it's one I've been curious about for a while now.

Are asteroids dead comets?

I know, lots of questions... ;)

Regards,
Eric