My upgrades to XNA 2D beginners tutorial

I used a XNA 2D beginners tutorial and changed it to a more generic and flexible code.
I also added explosions and sound.
The new classes I created can be used for any 2D XNA game.
The tutorial is here: http://creators.xna.com/en-US/education/gettingstarted/bg2d/chapter1Explanations and demo of explosions: http://creators.xna.com/en-US/sample/particle
The demo project with the new classes: http://www.megaupload.com/?d=NEMV4EF3
Screenshot:

Most of the code can't be figured from the screenshot.
I created some generic classes to represent static objects, moving objects, particles, and particles systems. I wrote the most important things about some classes:

• class GameObject2 : DrawableGameComponent
  • Represents a static 2D object
  • Has the following additional properties:
  • Texture
    
  • Position
  • Center
  • Rotation
  • Scale
  • DestinationRectangle
  • CenterPosition
  • Active
  • SourceRectangle
  • Color
  • Effects
  • LayerDepth
  • SpriteBlendMode
  • Has 8 different constructors for different purposes
  • Overrides Draw() method
    
  
  
  
• class MovingGameObject2 : GameObject2
• Represents an 2D object that moves
• Has the following additional properties:
• Velocity
• Acceleration
• RotationSpeed
• TimeSinceInit
• Overrides Update() method
  

• class Particle2 : MovingGameObject2
• Represents a 2D particle like in an explosion
• Has a Lifetime property
• Overrides Update() method
  

• abstract class ParticleSystem2 : GameObject2
• Represents a 2D particle system that can be used for explosions, smoke etc.
• Has the following protected parameters:
• rangeParticlesPerEffect
• rangeVelocity
• rangeAcceleration
• rangeRotation
• rangeRotationSpeed
• rangeScale
• rangeLifetime
• Each new particle gets a random value for each parameter from its range
• Overrides Draw() and Update() methods