Gamercow, about the asteroid belt... I don't claim to be an expert in astronomy or physics or anything, so you've probably got me. My thinking was that if the planet was sufficiently devastated (thus reducing its mass and therefore its gravitational field) and the debris was expelled with sufficient force, it might escape the orbit of the planet but not the orbit of its star, and end up as an asteroid belt. Since I did say that there was enough of a planetoid for the skeleton to cling to, I can see that a ring might have been more logical. Hardly the most unrealistic thing in the story, of course, but if you feel like sharing more on how these things really work I'd love to hear it. I doubt I've blown up my last planet, and I want to do it right next time.
I saw a very interesting show on the science channel about moon formation that covered material related to this. If I remember correctly, according to the show, both our moon and Saturn's rings were formed by planetary collisions that flung debris up. The angle of collision changed the result. In our case, the moon formed, which is getting further and further away from the planet and will eventually escape the earth entirely (it'll take a very very long time, it's moving at a rate of inches per year).
Shortly after the moon formed, it was much closer, thus appeared much bigger, and its gravitational pull was much more powerful, causing havoc on the surface. Apparently the moon is important for the formation of life on our planet, because it acts to stabilize the tilt of the planet, keeping it at 23 degrees and keeping the climates relatively constant, while planets without moons can suffer significant tilt wobble that would make a planet pretty much unlivable. Right now it's sheer coincidence that the moon and sun appear the same size from our point of view, making for very unlikely full solar eclipses where they match up nearly exactly. When the moon gets further away it'll no longer be able to cover the sun completely and a full solar eclipse will look like a ring.
In the case of Saturn, the debris wasn't flung far enough away to escape orbit. In fact it is slowly, slowly falling back down to the planet, but again it is at a very slow rate as it's velocity prolongs the fall. Eventually it'll all be reabsorbed back into the planet mass.
And, with all of this, keep in mind that I saw this weeks ago, and I'm not sure what their sources are. That was the material that seemed to make sense to me. There was some questionable material in there where one "scientist" claimed that the moon acted as an asteroid shield to protect the planet's life. Considering the relative size of the earth and moon, I am skeptical of that. Even she admitted that "it may not be likely, but it would've just had to save the earth once. There would be no evidence of such a moon collision." And if there's no evidence to base your conclusion on, it's not really science, it's just making crap up..