Avril - The Best Damn Thing
Gaga - The Fame Monster
Kesha - Animal
Fall Out Boy - Save Rock and Roll
My Chemical Romance - The Black Parade
Tokio Hotel - Scream
Britney - Femme Fatale
Rihanna - Good Girl Gone Bad

In The Zone
College Dropout
True Blue

For my fave Beyoncé, I'd probably say 'I am... Sasha Fierce' since it's the easiest to digest. If you enjoy the uptempo fun tracks, then listen to 'B'Day' and Self-Titled; if you're feeling the ballads more, listen to '4' and 'Dangerously In Love'! You won't be disappointed!

Taylor Swift: Definitely 'Speak Now' since it's the most Taylor Swift a Taylor Swift album can get.

Britney Spears: Three words: IN THE ZONE!!!

Madonna: The Immaculate Collection.

Gwen Stefani: Love. Angel. Music. Baby.

Britney - In The Zone
Kelly - Breakaway
Lily - Its Not Me Its You

Kanye West: The College Dropout.

Lil' Kim: The Notorious K.I.M.

Christina Aguilera: Stripped/Back To Basics.

Tony Bennett: Cheek to Cheek.

BTW is Gaga's best work, but TF(M) should be the starter.

Rosso Relativo if they seem to need a beat to enjoy foreign music, else Alla Mia Età.

For Xtina I'd say her greatest hits, everyone has a different opinion on her best album... So depending what you're into on that.

Overall I'd say Stripped.

Breakaway

The Fame for Gaga

Fever for Kylie

Teenage Dream for Katy

GGGB or Loud for Rih, probably Loud

In The Zone for Britney

Warrior for Kesha

Demi

Greatest Hits Chapter One

Teenage Dream of course, quintessential KP!

Red-sus.

Its my favourite album. The concept is brilliant and executed so well. No two songs really sound the same and in that there is so much variation in the style that listeners can decide which they like better and move on from there. I think its a lot more ambitious than it gets credit for and honestly even the weaker moments are completely necessary in some ways. Plus its pretty much a summation of who she is as an artist and a songwriter and the many emotions and stories that she loves to create songs about.