Is there any way to change graphical setting in Dark Souls: Prepare to Die Edition? :)

Dark Souls: Prepare to Mod Edition?

There is no texture quality option. That being said, there are texture packs on the Nexus, where peshmi linked you. Also don't forget to install DsFix in order to unlock the framerate and the rendering resolution, which is also locked by default (at something like 1280x600, regardless of the display resolution you select).

edit : post here if you need any help installing or setting DsFix

Thanks for answers. I want to lower the settings, because I have super-duper-hyper-low-end PC at the moment.

The game wasn't optimised for graphical options.

No way to lower the graphics settings, but you can definitely bump up certain aspects (grass, buildings etc.) via nexus.

You can change the resolution, antialiasing, and motionblur using DSFix.