Under the "Forward Zone" you should create a primary zone that reflects your registered domain name, i.e. - "mydomain.com". Under that zone two records should be automatically entered your SOA and the Name Server record. You then should create a reverse Primary zone that reflects your LAN subnet, i.e. - 192.168.1.X.
In your primary forward zone create a Host record or "A" record that points to DNS IP (server's IP) and check the option to create a reverse pointer for that record
If you are running mail servers under the same domain - i.e. "mail.mydomain.com" then create a MX record that points to "mail.mydomain.com". If your mail server has an IP other than you server then create a HOST record for that IP that points to the server and then create the MX record.
if you have aliases for your domain such as www.mydomain.com then create CNAME records that points to your server.