OK...to explain this a little better:

Two lead-off songs (tracks 1 & 2) that:

...so perfectly complement each other. The first song is great, and when the second one gets cooking, you think "Hell yeah! This is great too!", and you're glad you bought the album, regardless of whether you like any of the other songs or not.
...sound like they were written specifically to be back-to-back lead-off tracks on the album.
...even sound like they may have been recorded live in the studio, one after the other, without any over-dubbing or additional tracks added on later.
...when you hear the title of one, you can't help but think of the other.

Having said all that, I'll name some favorites from my own collection:

We Will Rock You/We Are The Champions - Queen (from News Of The World) (kind of an obvious choice, but I love Queen)
American Music/Out The Window - Violent Femmes (from Why Do Birds Sing?)
1999/Little Red Corvette - Prince (from 1999)
Detroit Rock City/King Of The Night Time World - KISS (from Destroyer)

Let's hear yours!

Iggy and The Stooges - Raw Power = 1)Search And Destroy 2)Gimme Danger

Nirvana - Nevermind = 1) Smells Like Teen Spirit 2) In Bloom

Aerosmith - Rocks = 1) Back In The Saddle 2) Last Child

Radiohead - The Bends = 1)Planet Telex 2) The Bends

Black Sabbath - Paranoid = 1)War Pigs 2) Paranoid

U2 - The Joshua Tree: 1) Where the Streets Have No Name, 2) I Still Haven't Found What I'm Looking For

Here's some all over the map responses from the top of my head

Down - NOLA
1. Temptations Wings 2. Lifer

NWA - Straight Outta Compton
1. Straight Outta Compton 2. F the Police

Sunny Day Real Estate - The Rising Tide
1. Killed By an Angel 2. One

Urge - Receiving the Gift of Flavor
1. Brainless 2. All Washed Up

Downset - Do We Speak A Dead Language
1. Intro 2. Empower 3. Eyes Shut Tight

GnR - Appetite
1. Welcome To Jungle 2. Its So Easy

311 - Music
1. Welcome 2. Freak Out

311 - Grassroots
1. Homebrew 2. Lucky

Rage Against The Machine
1. Bombtrack 2. Killing in the Name Of

Oh, well, I've got other stuff to do, hope someone is intrigued by my choices.

My Morning Jacket - At Dawn
1. At Dawn 2. Lowdown

Doors - Doors
1. Break On Through 2. Soul Kitchen

Elton John - Madman Across The Water
1. Tiny Dancer 2. Levon

The Band - The Band
1. Across The Great Divide 2. Rag Mama Rag

Pearl Jam - Ten
1. Once 2. Even Flow

Pink Floyd - Dark Side Of The Moon
1. Speak To Me 2. Breathe

Prince - 1999
1. 1999 2. Little Red Corvette

Radiohead - OK Computer
1. Airbag 2. Paranoid Android

Planes Mistaken for Stars - Knife in the Marathon (EP)
1. Scratching Pounds 2. Leaning the Room

Hum - You'd Prefer an Astronaut
1. Little Dipper 2. Pod

Hum - Electra 2000
1. Iron Clad Lou 2. Pinch & Roll

Sunny Day Real Estate - second album (the pink album)
1. Friday 2. Theo B.

Archers of Loaf - Icky Mettle
1. Web in Front 2. Last Word

Poster Children - Daisy Chainreaction
1. Dee 2. Cancer

I'm sure there are a lot more in my collection, but these are the first few of the top of my head.

Motley Crue: Shout at the Devil

Shout at the Devil, Looks that Kill

Tried to limit it to 1 CD per (if I didn't you'd see about 7 Tom Waits CD's there)

Tom Waits - Mule Variations
1. Big In Japan 2. Lowside of the Road

Elvis Costello - My Aim Is True
1. Welcome to the Working Week 2. Miracle Man

The Rolling Stones - Beggars Banquet
1. Sympathy for the Devil 2. No Expectations

I'll be cliche and say:
The Beatles - Sgt Pepper
Sgt Pepper -> With a Little Help From My Friends
is awesome

Rush - Permanent Waves 1. Spirit of Radio 2. Freewill

Semisonic - Feeling Strangely Fine

1. Closing Time 2. Singing in My Sleep

Pearl Jam - Vs.
1. Go 2. Animal

Led Zeppelin 4
black dog, rock and roll

Massive Attack, Mezzanine
1. Angel, 2. Risingson

Airbag/Paranoid Android

You guys took most of mine aleady!

Pedro The Lion's "Control"
1. Options
2. Rapture

Tool - Aenima

1. Stinkfist 2. Eulogy

Big Star - #1 Record

1. "Feel"
2. "The Ballad of El Goodo"

The Rolling Stones - Exile on Main Street:

1. "Rocks Off"
2. "Rip this Joint"

Chevelle - Wonder Whats Next
1) Family System 2) Comfortable Liar

Andre 3000 - The LOve Below
1) The Love Below (its an intro but more like a short song)
2) Love Hater

Thrice - The Artist in the Ambulance
1)Cold Cash and Colder Hearts
2) Under a Killing Moon

Probably the correct Rush answer, but perhaps "Subdivisions" > "The Analog Kid" from Signals have a little more thematic flow between the songs.

Of course, "Force Ten" > "Time Stand Still" is a nice start, too...

Call me old school, but

Thunder Road // Tenth Avenue Freeze-out

Judas Priest - Screaming for Vengeance
1. The Hellion
2. Electric Eye

(also an awesome concert opener)

R.E.M. - Life's Rich Pageant
1. Begin the Begin
2. These Days

Iron Maiden - Killer

1. Ides of March - 2. Wrathchild

The White Stripes - Elephant
1. Seven Nation Army
2. Black Math