Okay, that helped a lot, and I also realized I missed a few imortant .update lines.
Anyway, it's working now, so thanks for the help.

Here is the complete script, anyone can feel free to use it.
CODE
class Scene_Splash < Scene_Base
def start
super
SceneManager.clear
Graphics.freeze
create_background
@frames = 0
end
def create_background
@sprite = Sprite.new
@sprite.bitmap = Cache.picture("Untitled")
end
def update
Graphics.update
Input.update
if Input.press?(:C) or @frames > 320
Graphics.fadeout(20)
SceneManager.call(Scene_Title)
end
@frames += 1
end
def dispose_background
@sprite.bitmap.dispose
@sprite.dispose
end
end
module SceneManager
def self.first_scene_class
$BTEST ? Scene_Battle : Scene_Splash
end
end