Since I am Dutch and mostly visited Dutch themeparks, I've ridden a lot of the oldschool ones, however I've not been on many new generation ones yet. My number 1 is a world class one though, and wins by a massive margin:
1. F.L.Y.
2. Big Thunder Mountain Railroad (DLP)
3. Rock n' Roller Coaster (DLP)
4. Colorado Adventure
5. Xpress (before it was Platform 13)
6 Vogel Rok
7. Revolution
8. Python
9. Robin Hood
10. Raik
...and lower on the list some more oldschool family coasters, boomerangs and SLC's.