Setting up DNS correctly

[otherjohn]

Hi all,
Ok I have installed ISPConfig on a Linode Ubuntu server. My question is, I suspect I need to use linode's nameserver for my DNS handling, but I am not sure if that is correct.
How do I setup my MX records.

For each virtual host, is it as simple as setting up the DNS in linode then setting up the site in ISPConfig3? Is there a way I can setup the DNS in ISPConfig3 and it automatically writes it to linode? I see a plugin that does this but is only creates a copy, not a master.