I was never in the habit of watching Deep Space Nine when it was airing for the first time, but all of the episodes I caught here and there were from the later seasons. I just watched "Heart of Stone" in which Kira is trapped in a rock fissure on a moon and Odo must figure out a way to save her. Since I started rewatching the series, this is the first episode I remember watching previously. There is also a scene in the following episode, "Destiny," that I recall.
In other milestones, I've also watched the most boring episode of DS9 to date: "Distant Voices." This episode takes place entirely inside Bashir's brain, so there you go.
Some quotes from recent episodes that I enjoyed:
Odo: Well that's an interesting way of scrambling a signal.
Garak: Yes, I thought you might appreciate it on an aesthetic level.
Wormhole Alien (in the form of Kira): Linguistic communication is ... exhausting.