Capcom Classics Collection Vol. 2 Cheats

Highlight Ryu and hold for 3 seconds then,
Highlight T.Hawk and hold for 3 seconds then,
Highlight Guile and hold for 3 seconds then,
Highlight Cammy and hold for 3 seconds Finally
Highlight Ryu again and hold for 3 seconds then
Press all 3 punches and Start at the same time at the end of you counting.

There is a hidden boss to fight against in this game called Akuma. To get to him, you must play through the one player mode with any character and get at least 3 perfects and don't lose (you may not use any continues) When you get to M.Bison, Akuma will appear and you will face him instead. Akuma is very hard to beat and has all of Ryu and Ken's special moves, plus an air fireball and a teleport. He doesn't have a super combo though. If you manage to beat him you will get a slightly different ending than usual.