I had a similar problem with my home network, The XP boxes you have will want to be the Browser master and the win 2k box that is probably removed from the network from time to time thinks it should be the master browser. The IP addresses you reported are placed ther by the System to resolve browser conflicts from the foreign computer. XP will always win and the 2k box is disabled effectivly by the system. I will give the link to my discussion below, I never did get the ICS (internet connection sharing) to work I did however discover a redundant workaround that is still working just fine. Good luck... read my thread as I learned a lot from it.

http://www.antionline.com/showthread...930#post832930