If I actually had to line them up by ranked episode it probably wouldnt be top 5. So a bit of an exaggeration. But I would probably still have it in top 10-15. I think people tend to forget that a lot of the big moments in GoT happen in the same episodes. The show tends to give you 4-5 plodding episodes and then hit you with 15 big moments in one episode only to plod a bit again.
For this reason a lot of lists I see tend to have some combo of "Battle of the Bastards", "Winds of Winter", "Hardhome", "Rains of Castamere", "Blackwater", and "Baelor" somewhere in top 5. And it is because those episodes hold the shows "big moments" and often more than one of them. That is obviously more than 5, but everything after that tends to be different or personal preference (at least in conversations or lists that I have seen)
Last nights slow crawl to the throne and Daemon's kill shot I think are up there in some of the best scenes in show history (Daemon is far and away the best season 1 character to me). And the confusion over the prince who was promised conversation was a terrific way to end the season. There was also lots of really subtle and brilliant moments in the dinner scene. It simultaneously humanized and villianized multiple characters.