One song!? It's almost imposible too choose
Pokemon-Dialga and battle Palkia
Pokemon Victory road
Pokemon D/P wild pokemon battle
Pokemon Team galaxy battle
Pokemon: Route 1
Pokemon main them
Pokemon center ¿?
Yoshi Island (flower garden)
Yoshi Island: Obstacle track
Yoshi story: Ending
Metroid prime: menu
Super metroid: Ridley battle
Metroid main theme remix
Metroid: Samus theme
Mother 3: You call this an utopia!?
Mother 3: Unfounded revenge/smashing song of praise
Kid ikarus: Nes Medley-
Star fox: Wolf theme's 64
Star fox: Area 6
Star fox: Corneria
LoZ TP- Main theme (Hyrule field)
LoZ Main theme
LoZ OoT medley
LoZ OoT hyrule field
LoZ- Wind waker
DKC: Bramble blast
DKC: Overworld
Kirby superstar: Gourmet race
Kirby superstar: Metaknisht's revenge
Kyrby's airide: Checker knights
F-Zero: Mute city
F-Zero-X : Cliimb! And get the last chance!
FE- Sacred stones- Combat preparation
FE- Battle
FE- Ike's theme
Pikmin: main theme
Pikmin: main theme
Golden sun: battle theme/ final boss
MGS- Encounter
MGS-Yell (dead cell)
MGS-Theme of tara
MGS-Love theme
MGS- Cavern
MGS-Calling to the night
Sonic- Green hill zone
Mushroomy kingdom
SM world: title theme
SM world: castle theme
New SM: Main theme
SM sunshine: Both
Brawl main theme + All of the remixes (FD, SSE desert area, menu...)
SSE: Subspace Area
I thin i'm done
Really, brawl OST has coolness, awesomess, epicness and lot of nostalgic songs. Probably my favourite OST