Zeke, this has been a problem for a while. It has happened many times to me in the past when disconnected during battle and I KNOW i never hit Ctrl-G. Last night it happened again while fighting a boss i needed for a quest. I pressed Ctrl-G to see if i could get interface back. I did, but i could not see myself casting spells, see my or the enemies health circle, or the damage I did. After the battle, I couldn't move, which was very irritating cause i needed the tome in that room. I had to port back to commons area in order to move again.
I have noticed that usually a broken-chain icon shows up in the lower right hand corner right before it.
On one occasion I was in Ravenwood and nobody else was there, and could not go into any doors or leave.
I have since found that once the problem has occurred, quickly log out and back in.
I usually run two accounts, two computers. Since the farming deployment, on all occasions the no-interface has occurred on the computer that I type more on. Both have Windows XP SP3, both have 2G. Both have nVidia fanless cards, the one with no problems has GT 240, the other, I can't remember, maybe 7800? Both had the video drivers updated around the end of July, "when the seventh month falls".
Since the circular "chain" icon - especially the red version ( I think yellow means it's failing but not failed) - means your connection has failed, I always close the Wizard101 application completely and then restart. Even if the game takes me back to the schoolhouse view, I restart, since I don't trust things once a disconnect occurs.
Fortunately, with a MMO, all the game status is stored on the servers :)
While I don't work for KingsIsle, I do have some experience on other MMORPG's. What essentially happens is that the server stops communicating with your client. Your client shows the last thing that happened. Then it clears its screen and awaits new information from the server. Since the server is no longer providing any information, it can't update the screen with the stats of the wizards and enemies. So you have a blank screen and can't move or do anything except close your client and log back in.
If the battle isn't over, it will take you back to where you are, often without an interface. Eventually, the server catches up and sends you information. Meanwhile, three or four turns could pass or the battle could be over.
I don't know if this is exactly what happens here, but it's my guess that it's something like that.