7. Rose: Finish the arcade mode with M. Bison. That will unlock her.
8. Sakura Kasugano: Finish the arcade mode with Ryu. That will unlock her.
9. Seth: Finish the arcade mode with all 24 other characters. That will unlock him.
A useful tip at the start of the game: Beat the game with every (starter, like El Fuerte) character as you will need to use them to get more characters unlocked, and for Seth you will need to play through all 24.
The videos below show you how to unlock the Street Fighter 4 characters with easy to perfom tips, and character specific hints, to help you beat the game with every character.
This video shows some El Fuerte jumping kick tactics that you can use to defeat the game and the final boss with him. It also captures the moment that Seth is unlocked after playing through with all 24 characters.
In the case of the next video, we will show you some tips beating the game using Balrog. Remember to set the difficulty to easiest, and the rounds to one.
In this video for Blanka we will cover some strategies you could use to help you defeat Seth.
Street Fighter 4 character tips continue on Page 3 with Cammy.