The record companies haven't quite given up on audio-only opera recordings yet -- though they're getting there -- and there's a new release that looks like it might be good: Haydn's Orlando Paladino, conducted by Nicolaus Harnoncourt.
As I explained some time ago, Haydn was not a great opera composer: he never had nor developed the ability to create specific characterizations in music, which is the one thing any good opera compoer needs to be able to do. He was brilliant at conveying emotion in music, but the emotions of characters in Haydn operas are generic, unrelated to character or situation: there's the rage aria, the song of joy, or jealousy, or love; but nothing that can really convey the reaction of a specific person to a specific situation. Mozart could do that, and so could Handel, and so could composers who weren't anywhere near as proficient as Haydn -- Gluck, for example. Haydn's operas aren't dramas; they're just a collection of musical moments.
However, many of those musical moments are tuneful or clever or ingenious in some way, and Orlando Paladino has some of his best work in the field -- it's kind of a spoof of heroic operas, a mix of comedy and drama that anticipates Don Giovanni without being anywhere near as good. Harnoncourt has already done one worthwhile recording of a Haydn opera, his Armida with Cecilia Bartoli, so this new recording should be worth getting.