Artificial Ring System

[Fallingstar1971]

If left to their own devices, would all the space junk in orbit condense into a ring system like Saturns?

Star

[MeteorWayne]

No, eventually most of the material will return to earth. The only exception might be the few dozen satellites in geostationatu orbits, but the total mass is very small.

[Saiph]

planetary ring systems are actually unstable. Saturn's rings will, over time (on the scale of a hundred thousand years or so IIRC) shrink and fall into the planet.

the debris in earth orbit would settle towards a ring pattern (due to conservation of angular momentum), but would likely fall out of orbit before that happens. We don't place much stuff up high enough for it to last that long.