This is a hard one. The episodes in the Darla arc in S2 all blur together for me, or one of them might be my pick. "Five by Five" is pretty awesome. "Spin the Bottle" is delightfully funny. "Damage" was a very good episode. That's as far as I can go for deciding.
Day 1 - favourite female character.
Day 2 - favourite male character.
Day 3 - least favourite character.
Day 4 - favourite episode.
Day 5 - favourite season.
Day 6 - favourite couple.
Day 7 - least favourite episode.
Day 8 - least favourite couple.
Day 9 - favourite villain.
Day 10 - something you liked that most people didn’t.
Day 11 - something you hated that most people liked.
Day 12 - least favourite season.
Day 13 - favourite character arc.
Day 14 - a scene that made you laugh.
Day 15 - a scene that made you cry.
Day 16 - something that made you think “WTF?!”.
Day 17 - saddest character death.
Day 18 - best “Team Angel” line-up.
Day 19 - favourite Cordy moment.
Day 20 - favourite Wesley moment.
Day 21 - favourite Gunn moment.
Day 22 - favourite Fred moment.
Day 23 - wackiest-looking demon.
Day 24 - a character who didn’t get enough screentime.
Day 25 - rec a fanfic or fanvid (or both).
Day 26 - something that you wish had never happened.
Day 27 - something that you wish had happened.
Day 28 - sexiest scene.
Day 29 - ickiest scene.
Day 30 - whatever tickles your fancy