The Beatles
Abbey Road/Sgt. Pepper's Lonely Hearts Club Band
Most of the Beatles' latter albums are fantastic examples of all that is good about music, but these two stand out from the pack. There are others that deserve mention, like Rubber Soul and The White Album, but these are probably the pinnacle of the Beatles' huge amount of work. The medley at the end of Abbey Road is just amazing, and really finishes the album with a bang, and Sgt. Pepper's is just greatness from start to finish. Seriously, now.

Joy Division
Unknown Pleasures/Closer
Joy Division is undoubtedly one of the most influential bands of the late 70s/early 80s. They kicked off the Post-Punk scene and later became the band that arguably began the nightlife/rave culture; New Order. With ridiculously good production, the songs don't even show age today. Ian Curtis' haunting lyrics and vocals never leave me.

Pink Floyd
Dark Side of the Moon/Wish You Were Here
Arguably one of the greatest rock bands of all time, and two of their best albums. Most people list DSM as their best work, but WYWH is just as good, if not better.

The Velvet Underground
The Velvet Underground & Nico
One of the most influential bands ever. As Brian Eno once said, only a few thousand people bought the CD on its release, but almost every single one of those people was inspired to start a band and make their own music.

Wilco
Yankee Hotel Foxtrot
Has to be heard to be believed. It's just a fantastic CD and unlike a lot of other stuff. It was at first deemed to be so inaccesible for casual listeners that the label refused to release it, big mistake on their part.
Seconded.

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