Cool idea! I thought you first meant 50 songs one for each year so I was like that's easy. 50 for each year is a bit more.
The first song I thought of was MMMbop
That's 1997 for me atleast.
Some doubles and a little mix of everything including some Rock and even Punk:
Hammerfall - The Dragon Lies Bleeding
Hammerfall - Hammerfall
Bruce Dickinson - Accident of Birth
Bruce Dickinson - Freak
In Flames - Dialogue with the Stars
In Flames - Food For The Gods
Metallica - Where the Wild Things Are
Nightwish - The Carpenter
Rammstein - Engel
Rammstein - Du Hast
Rhapsody - Land of Immortals
Stratovarius - Black Diamond
Symphony X - The Accolade
Symphony X - Sea Of Lies
The Offspring - The Meaning Of Life
Foo Fighters - Everlong
Foo Fighters - My Hero
Foo Fighters - Monkey Wrench
Dimmu Borgir - Mourning Palace
Machine Head - Take My Scars
Testament - Demonic Refusal
Deftones - My Own Summer
Dream Theater - Hell's Kitchen
Edguy - Wings of a Dream