Art rock? The choices there seem like sort of a mix between prog rock (Pink Floyd, Rush, King Crimson, Yes, ELP) and cheese-rock (Styx) and others that are much harder to categorize, like Beefheart and ELO and Procol Harum.
When I was like 12-17, I listened to a LOT of Yes and Emerson, Lake and Palmer (and Powell). They've largely fallen off my rotation list (well, almost completely), but my appreciation for bands like ELO, Pink Floyd, and Beefheart has either remained steady or gradually increased. I think the laurels heaped upon Pink Floyd for "Dark Side of the Moon" and "The Wall" are somewhat overdone, esp. considering that their early work is so utterly fantastic. Yes, I have PF's popular stuff, and I do really like it (esp. Dark Side), but still, "Piper at the Gates of Dawn" and "Ummagumma" and stuff like that are pretty amazing. ELO's Jeff Lynne is pretty much a genius. I find even their underrated album "Time" to be something just shy of real genius. A great repeat listen.
But now, when I think "art rock" my favorite bands are largely those like Wire, Pere Ubu and Sonic Youth.