This is difficult, I must admit.
I'll go with:
1. One Winged Angel (FFVII)
2. Liberi Fatali (FFVIII)
3. To Zanarkand (FFX)
4. Searching for Friends (FFVI)
5. Eternity ~Memory of Lightwaves~ (FFX-2)
6. Aeris' Theme (FFVII)
7. Terra's Theme (FFVI)
8. J-E-N-O-V-A (FFVII)
9. Dancing Mad (FFVI)
10. (either) Fight with Seymour (FFX) (or) Clash on the Big Bridge (FFV)
Of course, this list can change very easily.
