Re: Saturn's rings.. Tombstone for the dinosaurs?
A moon that broke up under tidal stresses by getting to close to its parent planet (the Roche Limit) would be unlikely to have any components that would be at a velocity capable of escaping the gravity of the parent planet. The pieces would, as they have, drift slowly around the planet at varying orbital speeds. So I doubt that chunks of any lost moons of Saturn could have attained the delta-V required to drop to an intersect path with Earth's orbit.