Some of my favourites:
- Ninja Gaiden - 4-2
- Arkanoid C64 Version
- Castlevania - Stage 3
- 1943 - Mission Theme
- Turrican - The Deep C64 Version
- Double Dragon - Title Theme
- Double Dragon 2
- Mercs - Mission 1 Arcade Version
- Metroid - Kraid's Lair
The greatest main theme of any game:
I can't believe I need to add Zelda
Or is it just too obvious?
When things get quiet, I can still hear that song 30+ years later.