Sonic's been responsible for some of the best music from games EVER! This is my favourites because they all rock overall, but these are my favourites. This is "My Top 5 Favourite Music from a Sonic Game"
Can You Feel the Sunshine - Sonic R (Sega Saturn)
Spagonia (DAY) - Sonic Unleashed (Playstation 2, Playstation 3, Wii, XBOX360)
Green Hill Zone - Sonic 1 (Sega Genesis)
Seaside Hill - Sonic Heroes (Playstation 2, XBOX, Gamecube, PC)
City Escape - Sonic Adventure 2 (Dreamcast)
I couldn't really think up much to say but it's all good here. Tell me yours in a comment but this is all my favorite Sonic songs.