Confusing, As stated Who you are logged in as on the win2k box is of no importance.
However the problem is most likely with Samba. Just remember the Guest account thing for troubleshooting later.
Are you using the smbmount package?
Linneighborhood is just a GUI for samba. Try getting it to work on the command line first, then use Linneighborhood.
For Windows clients to access shares on a win2k host you have to have the same network name and password as a user of the host machine with permission to the shares, or have the guest account enabled and have shares shared to everyone.
In linux you have to use samba.
Just share something read only like a temp folder with a file in it or something to everyone, and enable the guest account until you get something working. Then you can configure your shares and user permissions.
This is about smbmount...
http://us2.samba.org/samba/smbfs
This is how to logon, User name, Netbios, Workgroup, Password, etc...
http://us2.samba.org/samba/docs/man/smbclient.1.html