OK Computer by RadioHead.
Wish you were here by Floyd
Excellent choices. But, despite my undying love for all things radiohead, i'd have to say WYWH. It's just... a really f***ing strong album! I love each and every second of it. And Wish You Were Here is probably my favourite song of all time.

Honorable mentions:

John Mayall's Bluesbreakers feat. Eric Clapton AKA Beano - The album that revolutionized rock before hendrix came along. Ok, maybe that's a bit strong, but for what it was, this album was groundbreaking at the time, and is still breathtaking today. And it features Eric's best lead guitar work, despite him being very very young at the time.

Animals, Darkside, The Wall, Division Bell etc - It's the floyd. 'Nuff said. And i really did enjoy The Division Bell and Momentary Lapse, despite the 'It isn't floyd without waters' comments that float around.

The Beatles = Revolver - I always thought this was a stronger album than Sgt Peppers. Maybe not as groundbreakingly important, but more enjoyable to listen to. That's not to say Sgt Peppers isn't f***ing amazing! But i just prefer Revolver.

I could go on forever like this, so i'll cut it out now.