Suggestions for Recovering from messed up upgrade

[Malcolm Fitzgerald]

When I upgraded from 5.x to 6 I messed things up. The first problem 
that I had was that I couldn't access localhost in my web browser. I 
made changes to many config files as I followed suggestions. Now it is 
worse, the NIC is disabled at startup, so I have to pop into KDE 
control center and enable it if I want to access the net.

Everything else works nicely.

What is the easiest way for me to start with a clean slate?

malcolm