I vaguely recall the Punch out (NES version) having decent music, also Contra 3 the Alien Wars, that was an awesome game and really good music for its time as well.
I kid you not, I'm looking at my copy sitting next to the SNES by the living room TV. I feel the exact same way, man...when you want to remember what it's like to be "free", DKC2 is the way to go.
Also: MK Deception. Best character select screen/MK music ever, IMO. I can't remember another MK game where I was always so attentive to my soundtrack.
Streets of Rage 2
Mega Man X
Doom
Sonic & Knuckles
Super Mario Galaxy
Legend of Zelda: Link to the Past
Donkey Kong Country
God of War
Star Wars: Knights of the Old Republic
Skyrim
DKC soundtracks
MK game soundtracks(I have them, well MK1, MK2 and MK3 and MK4)
MK Mythologies
Perfect Dark sound track
Doom soundtrack
MotoHeroz Soundtrack
Trials Evolution(not the intro music, but rather the music in the game itself stages)
All Star Baseball
Burnout 3
Split Second
Killer Instinct I've always liked the music more then the game itself
Chrono Trigger is by far the best video game Soundtrack of all time.
2. Super Metroid (SNES)
3. The Legend of Zelda: A Link to the Past (SNES)
4. Mega Man 2 (NES)
5. Castlevania (NES)
6. Final Fantasy 6 (SNES)
7. Command and Conquer: Red Alert (PC)
8. Ninja Gaiden (NES)
9. Donkey Kong Country (SNES)
10. Final Fantasy 7 (PS)
11. Double Dragon (NES)
12. Metroid (NES)
13. Castlevania 2: Simon's Quest (NES)
14. Final Fantasy 4 (SNES)
15. Metroid (NES)