I went to the setup, and shaders was unchekced, so i checked it, pressed okay, and nothing happened! so i went back to setup, and it was unchecked. am i doing something wrong?

It seems like you are unable to run them with you current setup. Care to post your computer specs?

how do i do that (im not good with computers)

it means his graphics card isnt good enough to run shaders.
It's ok, I run without them. they lag you if your graphics card isnt good anyway.

oh okay

Hold the Windows button on your keyboard and hit R. Type "dxdiag" in the prompt, copy and upload the System page. We can tell if it's a problem or you just can't run it from there.

Yes, do that, because it may be your drivers what are causing the problem.
If you dont have the best drivers for your hardware then you might not be able to use it on full capacity.