Re: Stopping the device. Yes, you really should stop it before yanking out the cable, although as you rightly say if the drive isn't being read from or written to at the time, you're data should be safe.
Having said that, get into the habit of stopping the drive before you pull it out. There are many occasions I've looked at the lights on my USB data stick, noticed them go from fast flashing (drive activity) to slow flashing (erm, no drive activity), to then briefly being read from/written to again. Just in case, eh?
As for the rest of the questions, I'm not going to guess at that - I simply don't know enough about it.