I have to say, as a more-or-less lifelongish fan of Oscar Wilde (first read "The Happy Prince" when I was eight or nine), that the ending to Ernest is especially weak. I like the way he builds his house of cards in that play, and I like the dialogue, but (and I think I probably speak for a lot of Wilde fans here), the way he knocks the cards down really isn't all that clever or funny. For a smarter Wilde play, see "A Woman of No Importance", although his best works are his childrens' stories, "The Picture of Dorian Grey", and "Ballad of Reading Gaol" (although it is not, in fact, the case that "Every man kills the thing he loves".)

(Also I should mention that I recently reread "The Code of the Woosters" and laughed myself inside-out.)