There is a reconstructed AOTC soundtrack floating around out there that I occasionally use as background music. I don’t do that with any of the other prequels, so I guess that means that AOTC is my favorite of the prequel soundtracks. It also has perhaps my favorite end credits music (ANH might edge it out though).
A New Hope EASILY has my favorite end credits music. I attended a local symphony recently and they did the throne room till the end credits. It was truly incredible 😃