The Belkin router works for the other two PC's. As I said I
don't know how to look in the network areas (as I do in Windows) and
most of what I do is guess work. I think you may be correct that it
has something to do with the IP address. Something causes it to loose
it and when it needs to connect to the net, it can't.

I'll keep trying and 'pinging' and see if I can get to the bottom of
this problem. I'm having fun with Ubuntu and I'll eventually find my
way.