Ghosthunter is one of the best! That's true. Some time ago my top list was Black, God of War 2, GT4 and Shadow of the Colossus. Now I think I can add to this list Peter Jackson's King Kong: The Official Game of the Movie. Great game with amazing graphics. 3D ocean, real 3D light shafts like in X360 and PS3 games, high res textures (for PS2), good smoke and fire effects, a lots of foliage (in some places it even interacts with player, his friens and enemies, and also in many places player can burn grass) , absolutely great motion blur, All this makes this game graphics in my opinion even better than Black. You shoud check this game. Here is a good example.what do you guys think was the most technically impressive game on PS2? Personally I say Ghost Hunter, it has high poly characters model, light map for flash light which is absent in all silent hill games on PS2, 3D water, individual grass that interact with the character, 480p + widescreen and advance post fx at the time. All of that and solid performance and I thought I was playing a high end Xbox 1 game. Many says GT4 since it got 1080i support and runs at 60fps with high quality car models at the time.
One more game with great graphics is Cal of Duty: World at War: Fina Fronts.