My top 5
1. Earthbound - Awesome!!! Awesome!!! I purchased all the Mother sound track and I listen to them all the time
2. Megaman 2 - I get many of the tunes stuck in my head. Great stuff!
3. Super Mario World - The castle theme is a fav, the others are great too.
4. Castlevania 3 - Sounds awesome on the famicom
5. DKC 2 - Probably stuck in my head, because I played it soo much when it came out.
I also love Super Metroid and Darius on the Pc Engine cd.