I think I have discovered an error with the information on the TCP/IP NetBIOS Helper service. It is an easy mistake to make however as the description of the service itself is misleading, Enables support for NetBIOS over TCP/IP (NetBT) service and NetBIOS name resolution.
If you are not using WINS (NetBIOS) for name resolution you can not access a server share by UNC name with this service disabled!
i.e. \\server1\share will not work.
Packet traces indicate that windows will resolve the name with DNS, then completely skips SMB to connect and moves on to http:\\servername\share (WebDav I presume). I have confirmed this on WinXP SP2 and SP3.
TekMason