Capcom added new content made specifically for the PlayStation 2, and later added into the PC and Wii releases.
Separate Ways, a five chapter minigame which revolves around Ada Wong's involvement in Resident Evil 4, and her connection to Albert Wesker, a former member of the Raccoon Police Department S.T.A.R.S., who is now attempting to revive Umbrella. During the minigame, the player can use a pump-action shotgun and a bowgun with explosive arrows, two exclusive weapons. The Japanese version of the minigame title is the another order.
Ada's Report, a five-part documentary, which analyzes Ada's relationship with Wesker and his role in the plot. Players unlock portions of the documentary as they progress through the Separate Ways mini-game.
New costume set, one of which portrays Leon as a 1920s mobster, and puts Ashley in an indestructible suit of armor. Leon's Chicago Typewriter also has a drum magazine as opposed to the regular box magazine.
P.R.L. 412 (Plaga Removal Laser), a laser gun which can be used to stun or kill an enemy. Unlocked by beating the "Professional" difficulty setting. With a tap it releases a bright flash that blinds the enemies temporarily and causes some damage. With a complete charge it creates a beam of light that can instantly kill any enemies caught in the beam. In the Wii version, the weapon fires a beam at every targetable object onscreen, including enemies and windows.
Movie Browser, a feature that allows the player to view cut scenes from both Separate Ways and the actual game. The feature is unlocked after a player beats the game.
Amateur mode, an easier difficulty setting which is exclusive to the Japanese and PC versions. In the PC version, a player will start the game with the shotgun already in their inventory on Easy mode.
A 16:9 anamorphic widescreen mode, for widescreen TVs.
http://en.wikipedia.org/wiki/Resident_Evil_4#Special_editions_and_bonuses
