On a lot of the planes now they are telling you to chuck the door out, not lay it on the seat (duh--at that point to h@@@ with denting the wing!).
At any rate, we've seen families moved out of those rows, we often try to GET those rows for the little extra legroom! About six months ago we were in the row in front of the exit row, and this family got on, car seat and infant in tow. As they were moving into the exit row I told them not to bother setting up the car seat, because they wouldn't be able to sit there. Sure enough a minute later a FA told them they'd have to switch, and we immediately volunteered to move back a row.
We've also seen a husband and wife moved, she didn't speak English, and when the FA told the husband that the wife couldn't sit in the exit aisle, he said "I'll translate for her" and was very nasty to the FA, and refused to move. I was sitting across the aisle and verbally "smacked him across the head" by saying "Not if you're DEAD you won't". He gave me this look that if he could have killed me on the spot with his bare hands he would have. At any rate, he got really beligerent, and the captain had to come back--basically told him to MOVE OR GET OFF THE PLANE. Turns out part of the problem was the wife was in an aisle seat and he wouldn't let her sit anywhere but an aisle seat less she come in physical proximately with an "infidel". Sorry if this isn't PC--he was a jerk. In all honesty, this was before September 11, I'm convinced that if it happened now, he would have been off the plane, period.
I've also seen a very frail elderly woman reseated--handled quite gracefully, they took her to first class!
Anne