Street Fighter Collection 2

Street Fighter Collection 2 (and not the Street Fighter 2 Collection as it's mistakenly called) is the American release of the Japanese release Capcom Generation 5: Dai 5 Shuu Kakutouka Tachi (カプコン ジェネレーション －第5集 格闘家たち－). In America it was only released for the PlayStation, but in Japan it was released for the Sega Saturn as well. It is a compilation of the following SF2 games:
 * Street Fighter II
 * Street Fighter II Champion Edition
 * Street Fighter II Turbo

CPU Battle Mode
To unlock CPU Battle Mode, finish Arcade Mode without using continues in all 3 games. CPU Battle will only be unlocked for the game you finished it in.

Remix Audio
The remixed audio is very likely the prorated music of the Neo Geo to Neo Geo CD by SNK, to unlock remixed audio, finish each game the first time.

Deluxe Vs. Mode
Successfully complete all three arcade modes (saving after each time). This allows a 2 player mode using any character from any version. A handicap can also be selected. This was later upgraded at Hyper Street Fighter II.