Which to use NFS or Samba?
In a closed network (where you know every device), NFS is a fine choice. With a good network, throughput it disgustingly fast and at the same time less CPU intensive on the server. It's very simple to set up and you can toggle readonly on shares you don't need to be writeable.
I disagree with Anders. v4 can be just as simple as v3. It only gets complicated if you want to start layering on security through LDAP/gssd. It's capable of very complex and complete security mechanisms... But you don't need them. They're actually turned off by default.
sudo apt-get install nfs-kernel-server
Then edit /etc/exports to configure your shares. Here's a line from my live version that shares my music:
/media/ned/music 192.168.0.0/255.255.255.0(ro,sync,no_subtree_check)
This shares that path with anybody on 192.168.0.* in a readonly (notice the ro) way.
When you've finished editing, restart NFS:
sudo /etc/init.d/nfs-kernel-server restart
To connect a client, you need the NFS gubbins (not installed by default):
sudo apt-get install nfs-common
And then add a line to /etc/fstab
192.168.0.4:/media/ned/music /media/music nfs ro,hard,intr 0 0
This is actually the NVSv3 client still because I'm lazy but it's compatible in this scenario. 192.168.0.4 is the NFS server (my desktop in this case). And you'll need to make sure the mount path (/media/music here) exists.
For a Mac, follow this: http://www.techrepublic.com/blog/apple-in-the-enterprise/mounting-nfs-volumes-in-os-x/
It's much more simple than some older tutorials would have you believe.
It might look more complicated than it really is but it's solid, predictable and fast. Something you can't level against Samba... At least, in my experience.
I recently tested the connection via SMB and NFS to my Synology NAS station. For me the NFS connection works two times faster than the SMB connection. Especially if you have to deal with 100 GByte of photos and music files in 1000 directories you will love the speed of NFS.
NFS (version 3) will give higher performance and is quite easy to set up. The main problem is the complete lack of decent security.
NFS (version 4) gives security but is almost impossible to set up.
Samba will probably be a bit slower but is easy to use, and will work with windows clients as well..