Can I skip someone in the post order?

1) Sue would still need to wait for Pam to post before Sue can respond, unless Pam gives Sue explicit permission to skip over her. Even if a question is directed at a single character, other characters involved might express interest in the question, become offended by the question, or add on to the question, so they need a chance to react to it as well even though it isn't directed at them.

2) Threadlog is just a list of threads you're currently involved in. The one here at WOLF is automated.
Pawprints is a term we use for a character tracker, it's basically a thread where you track various things for your character. At WOLF most people use their Pawprints to track trade progress, however, there are a few people who use it to track history or family.
I'm not familiar with Storybooks as an RPG term. I would imagine it's similar to either Threadlogs or Pawprints (or both?).

3) Images online are very difficult to govern, in our experience. We strongly encourage using only Creative Commons stock images and we have an "Art Credit" field in the profile to encourage giving credit where credit is due, however... it's very difficult to truly enforce it, especially when there are people online who just Google search images and don't even know themselves where the image originated. We strongly encourage not using images that are copyrighted and giving credit for said images, but it's not something we can police. Drawings we do enforce.

Shadow-posted! Fox covered it all. :)