The "Mario" games I've played in order (1 best, 20 worst):
1. Super Mario Bros. 3
2. Super Mario Bros. 4: Super Mario World
3. Super Mario Land 2: 6 Golden Coins
4. Super Mario Bros.
5. Mario Bros.
6. Super Mario Bros. 64
7. Super Mariokart
8. Super Mariokart 64
9. Super Mario Bros. 2: The Dream Machine
10. Super Mario R.P.G.: Legend of the Seven 11. Stars
12. Dr. Mario
13. Wario's Woods
14. Super Mario Land
15. Super Mario Bros. 2: The Lost Levels
16. Super Mario Bros. 5: Yoshi's Island
17. Super Smash Bros.
18. Mario Paint
19. Mario Party
20. Wario Blast