I love these games and I think the soundtracks are underrated as an essential part of their appeal. I’ll Start with one:
https://www.youtube.com/watch?v=Kk72RMv9d0s
Tube of Medusa from Ecco2: Tides of Time.
Personally, I think the Sega CD version soundtrack is… fine, but it has a different composer. If I remember correctly, it;s the composer from the first Ecco. In my opinion, it’s inoffensive, but completely forgettable.
EDIT: I have edited the topic to include older stuff.
NES is Contra Jungle
SNES is Simon’s Theme from Super Castlevania IV
N64 is probably most of F-Zero X
The 'Cube is rough since I grew up with it so I love a lot of it. Luigi’s Mansion, Mario Sunshine, Wind Waker, Twilight Princess. Too hard to pick.
TG16 is the original Bonk. That level 1 music lives in my head.