I definitely think that Henry did the right thing in not wanting to her be killed.
I totally agree that Henry was trying to stop Regina and in that it works. In only that does it work. I still hated it and hope that is the last time he calls her that. At least he called Emma his mom in the next sentence. It was a dramatic moment, but it just grated on me a bit especially since we know we aren’t going to be seeing Emma and Henry for awhile. I was looking forward to seeing Emma figure out how to be a mom.