Mesch and Supastveo, back to topic. Anyway, with Shaders 2.0, you might be able to activate everything (which is my case), but the game will be slow as hell.
With Shaders 3.0, as Skulfuk said, you might be able to activate every shader options without slowing the game.
For your information, there are graphic cards handling the Shaders 4.1.