Despite the fact you can ignore players in game, it would be nice if you could stop them from joining your fight. I have found the most common form of "harassment" in Wizard 101 is people joining battles and going away from the keyboard (or joining battles and fleeing) while you and your friends take on the monsters that they have dragged into your fight circle. It would be nice if you can block a particular player from entering a fight circle that you have started (not necessarily a fight circle that someone else has created).
Doing this would help drastically as the consequences of this happening have tended to be fights that take ten minutes or more, or you or your friends dieing due to extreme overwhelment.
Re: Fight Circle Sleepers - Some sort of protection
Yes this and the please ask before porting button are nessasary. I am tierd of dying because others have been rude and joined and left. I would love to lock who could join in a fight i start and if you cant a port and flee report should be possible