RE: emacs editing software not working
It seems your display variable is not set correctly. All locahost machines have it set to :0.0 by default. Yours is set to localhost:11.0. This is incorrect.
In a shell type; ( you do not need to be root )
This will show you what your display is currently set at.
You want to change it to :0.0, to do this type; ( you do not need to be root )
Now type emacs again in the shell and it should work.
In retrospect you can display all variables by typing;
Do not change any unless you know exactly what you are doing.