Originally Posted by Gibonius
I wish they'd have included his line about "Of all the things I've done, killing Aerys was the best" or however it went. He admits he's done some shit, but he gets judged by everyone for doing something essentially noble. And, something everyone else was on the same side of. Ned was a rebel, had sworn an oath to the king, then held Jaime to a higher standard (on a higher order oath, of course).
Ned didn't swear an oath. He was never Lord of Winterfell and Lord Paramount of the North until King Aerys killed Lord Rickard and Brandon, making him Lord. His House had sworn itself to the Targaryen dynasty. But, his father fulfilled that oath when he presented himself to King Aerys after Brandon was making threats against the Crown Prince. Oaths always have two sides. And when Aerys cooked Lord Rickard alive in his armor, it seems to me that Aerys broke any pact between the houses.
Now, Lord Jon Arryn and Lord Robert Baratheon, I'm not sure King Aerys did anything to breach their oaths.