ok it just suggests if you have the following::
load "dri"
load "glcore"
then you should remove them....if they aren't there at all, then you can look at it as all the less you have to edit

so don't get hung up on stuff like that, if its not there to remove then its not there, and thats what is required...
so all you have to mainly do in your config is the following::
1) make sure the above lines i just mentioned are not there if they are put a pound sign (#) in front of the line or remove it all together....ex -- > #Load "dri"
2) make sure in the same section you have Load "glx" which i noticed in your config that you already have it, so again one less thing to worry about....
3) and lastly, change the line that says:
Driver "nv" to say Driver "nvidia"
....after all that is done, save the file return back to your normal user, and type startx and see if you suceeded

..