Couple observations:
What part of the error message didn't you understand, exactly? It told you X11 was missing and how to get it back.
Secondly, how did you manage to do an Archive and Install without your dad's permission? Seeing as you now need his permission to re-install X11, how did you Archive and Install?
I am mostly interested as I have been known to write software and do tech support. I am continually amazed by the byzantine human/computer interactions that occur every day, here in the "future" world of 2006.