I love the episode in the fourth season, "Tabula Rasa" when he becomes 16 again and is a complete nerd. My fave line is when he and Gunn are fighting and Angel says, "My money's on the slave."
Thats actually "Spin The Bottle". "Tabula Rasa" is the episode in Buffy season 6 where Willow accidentally wipes all their memories.
Anya dying was done for Emma Caulfield as she told them she didn't want to return to Buffy spin offs or Angel again after the show, so they killed her to make sure of it.
Wes dying was really well done. It makes sense that in a battle with the ultimate tools of evil in the world, someone was going to die, and Wes had nothing left to live for, like he said to Illyria before the battle when he was tending her wounds, he could never have a perfect day again. The scene when Illyria becomes Fred once more for him as he died was really good.
Season 5 was one of my favourite seasons, not least coz Spike joined the cast (One of my 2 fave characters along with Faith). The Spike/Angel interaction was fantastic, like bickering little brothers. Nothing will ever come close to beating the Cavemen vs Astronauts arguement.
Spike: It's bollocks, Angel! It's your brand of bollocks from first to last!
Angel: You can't ever see the big picture. You can't see any picture!
Spike: I'm talking about something primal, all right? Savagery, brutal animal instinct.
Angel: And that wins out every time with you. You know, the human race has evolved, Spike!
Spike: Into a bunch of namby-pamby, self-analyzing wankers who could never hope to triumph against--
Angel: We're bigger, we're smarter, plus there's such a thing called teamwork, not to mention the superstitious terror of your "pure aggressors"!
Spike: You-just-want-it-to-be the way you-want-it-to-be.
Angel: IT'S NOT ABOUT WHAT I WANT!
[Wesley enters]
Wesley: Sorry. Is this something we should all be discussing?
Angel: No.
Wesley: It just...sounds a little serious.
Angel: It was mostly...theoretical...We...
Spike: We were just working out... Look, if cavemen and astronauts got into a fight, who would win?
Wesley: .....Ah. You've been yelling at each other for forty minutes about this?
Wesley: [thinks for a moment] Do the astronaunts have weapons?
Spike and Angel: No.
and it also has meaning later on before Fred is consumed by Illyria, when she is writhing and whispers "Cavemen win..."