This is a Ring galaxy that I've been working on. So far it looks okay, but the clouds don't seem right, I might mess with them a bit more. Criticism is always welcome! also, this image is less then half the size of the full version.
The core should be made of stars (like the arms) - right now it's just a yellow blob. I take it that you're looking at existing images of ring galaxies? (Hoag's Object is the most famous one, but there are others that can be found on a google image search for "ring galaxy")