Hi Randy,
This is from the top of my head, so I might be making some mistakes here. Another staff member will correct me if I'm wrong, I'm sure.
I believe that the big circle means that the topic starter has indicated that their question has been answered satisfactorily, and requests that a staff member marks te topic as resolved.
A small dot means that a staff member has marked the topic as resolved. This can occur multiple times by different staff members, and each time it will add another small dot. I will mark this current topic as resolved, and if another of my colleagues does the same thing, you can see that this
thread will have more than one dot.
If many of your topics are not marked as resolved, that just means we are lazy.
I don't know what you mean by colors. I think the only colors we use are beige and yellow. Or maybe the colors are different, I don't know; I'm color blind. Yellow folders indicate topics that contain new posts since the last time you viewed the topic, and beige folders indicate that no new posts have been added since you last viewed the topic, or since you've started your browsing session.