You need root account access to edit the smb.conf file, i.e. use:
$ sudo -i
# cd /etc/samba/
Then use vi or vim to edit the smb.conf file.
Here is a tutorial on using vi/vim:
http://www.cs.fsu.edu/general/vimanual.html
Are you in a root account or ubuntu user level account that?
Check the permissions on the /etc/samba/smb.conf file with:
$ ls -lt /etc/samba/smb.conf
You should see something like:
-rw-r--r-- 1 root root 10515 2007-04-15 07:56 /etc/samba/smb.conf
which means that only root account can edit/write the file
What "date" are you talking about? If you are talking about the date command from your terminal command line window issue the command:
$ which date
and you should see the directory location of the date command print out on the next line.
-- Tom