Very helpful comments. Thanks a lot!

I did set default gw 192.168.0.1 (that command in my last post was copied from an faq, sorry for the confusion).

I have a hub between the laptop and the winxp box. The winxp box has two netcards, one connecting to the cable modem, the other connecting to the hub. The laptop also connects to the hub to share the internet access. This set up worked when my laptop ran winxp. Would the hub be causing the problem?