Rotating / Aligning and Seperating

(I posted this like 20 minutes ago, thought all was well, came back to look at it, POOF was gone, I must have skipped a step)

I am pretty new to blender, and even 3d for that matter, so bare with me on this, thanks guys…

I had a ring modeled in 3d (a spinning ring, consists of an inner and outer band) to practice making photorealistic renders, and now I am trying to animate it and am having problems with certain things…
1.) I cannot get the ring to rotate on a straight axis, it always wobbles.
2.) The ring was modeled as two parts, but as one object I believe, so when I rotate the inner ring, the outer ring rotates as well, how do I seperate them?
3.) How in the world do you align objects relative to other objects (like the ground plane even) because I tilted the ring a while back for a photo, and can’t get it to lie flat again.

The file I am working with is

Again, thanks in advance guys, highly appreciate your input.