All port options grayed out

I recently used Retrospect to reinstall my OS 10.2.8 system after reformatting my HD. Everything went beautifully. Then I tried to upgrade to Panther and all went haywire. Finaly went back to 10.2x, but now I can't connect to the net (I'm using my wife's computer now). All of my options in the Network section of my Sys Prefs are now grayed out. I have thrown away all sorts of preferences, restarted, checked and rechecked the hardware, router, DSL modem, and my Network Utility keeps crashing. The Internet Connect application is set properly, but no help. I think that the computer refuses to recognize any ports (specifically the Ethernet). What is going on??? I feel like I own a Windows machine!!! Any advice is welcome!!
P.S. this is my second very very bad experience with Panther. Bad bad kitty!!!