This is actually quite easy to do:
You can set up the .blend file that Blender default opens.
If I wanted to set up default shaders, I would simply go to the shaders tab, and select the shader I want to be the preset.
Same goes for the textures: go to the textures tab, and select the default Blender texture I would want to be the preset.
Now comes the magical part:
1) Save the .blend as (default.blend) or whatever.
2) Press CTRL+U to give you the "save startup file?" menu, and select it, or for the python-lovers' sake:
3) Re-open Blender, and discover the new changes you have made.
This is how to preset default settings in Blender (not modifiers or unset simulators), and I hope it helps all that read this post!