1. What exact version of Windows on all machines, please? If XP, please state Home or Pro, and whether you have run the networking wizard, and exactly what choices you made when you did it - and whether SP2 is installed or not.
2. Zone Alarm can and will block filesharing over TCP/IP. Disable it till you get this solved.
3. How to install NetBEUI on XP:
http://www.microsoft.com/windowsxp/p...ng/netbeui.asp