Demon Days is almost certainly the best — the one with less filler, the most coherent narrative throughline (Really, what is going on in Plastic Beach?), and, of course, the one with all the hits*. I’m not sure it’s my favorite, though. Maybe I’ve listened to it too much, but I find myself revisiting Plastic Beach more often these days.
In terms of best song, holy moley, that’s a hard one. I want to say it’s either “Dirty Harry,” “Don’t Get Lost in Heaven/Demon Days” or maybe “Clint Eastwood” off the first album? Again, I’m trying to be subjective, but objectively, my favorite is either “Do Ya Thing,” which I just utterly adore, or “To Binge.”
(Edited to add: Or “Hong Kong”! I always forget “Hong Kong,” but I love that song to pieces. Classic melancholy Albarn.)