I know you said only answers, not questions, but your posting was not very clear on the overall goal. Do you want to share folders between the Debian boxes? Do you want to share folders between the Debian boxes and Microsoft? Or both? If it is both you would probably be best off setting up samba. If it is just between the Debian boxes my opinion is to use NFS. From a security standpoint and setup I feel it is easier to understand. In either case you will need to make some decisions on setup and security. There are two HOWTOs written on this subject that should be able to help you out.
. Samba is normally installed with documentation so you can probably find lots of docs in /usr/share/doc/samba-2.2.12. You may have a different version than 2.2.12 so just go to the doc directory and look it over.
The file you will need to edit for samba is normally located at /etc/samba/smb.conf. The file to edit for NFS is /etc/exports. You must be logged in as root to edit these files. I do not understand why you are having trouble editing this file as root. The root user overrides all permission settings. If you want help with this we will need to know which editor you tried and the exact messages you are getting.
On the connection problem when using swat you will need to check two things. First make sure the swat service on port 901 is not commented out in the /etc/services file. Second you have to set up an entry in inetd or xinetd. These are the internet daemon or extended internet daemon respectively. What they do is start up the swat service when it is requested via a browser. The entry in /etc/inetd.conf should look something like this...
swat stream tcp nowait.400 root /usr/local/samba/sbin/swat swat
The /usr/local/samba/sbin/swat will most likely be different. Type which swat
at the command line to find out the correct path for swat and enter that instead of /usr/local... If you have xinetd then there will be a file in the directory /etc/xinetd.d named swat with similar settings.
Once everything is set up for NFS or SMB you will need to start the daemons. I have not used a Debian distribution so I don't know exactly what to tell you. There will most likely be a GUI and/or command line way to get them started.