As to Gingrich resigning as a House member, so did Denny Hastert when he wasn't chosen as Minority Leader in 2007 like Pelosi was in 2011. Having the old leader in the background of the new leader can be a distraction. Whatever the merits, or demerits, of Hastert's decision, noone says he "resigned in disgrace."
Gingrich resigned as a House member the day after his own re-election.
Hastert resigned as a House member eleven months after his own re-election.
But your logic seems to be that since both men left the Speakership in
somewhat comparable circumstances, that if Gingrich was considered to have resigned in disgrace, then so must Hastert. Given that the circumstances were in fact quite different, your logic doesn't really work out.
