Build DNS in Server 2003 R2 for DMZ

Before I jump in, what are the things I need to consider.

Here are  the file containing the zones that I need to register (had to change the terms to 'test'). Is this sufficient? Please advise.

$TTL 300
testrad.com.      IN      SOA     mx-gw5.testsp.com.  sagroup.testtek.com.  ( 2011022500 3600  600    1209600 300  )
                NS      mx-gw5.testsp.com.
                NS      mx-gw6.testsp.com.

        A       204.154.142.77

        MX      100     testrad.com.s5a1.psmtp.com.
        MX      200     testrad.com.s5a2.psmtp.com.
        MX      300     testrad.com.s5b1.psmtp.com.
        MX      400     testrad.com.s5b2.psmtp.com.


;testaccess              A       53.117.206.67
;testaccess              A       55.197.211.68
testmsftp01              A       53.117.206.9
sss1                    A       53.117.206.67
sss2                    A       55.197.211.68
inside                  A       55.223.178.42
ftp01                   A       53.117.206.70
www                     CNAME   redir.digtestgrp.com.

;  Delegated sub-zone:  *.testaccess.testrad.com.
testaccess.testrad.com.            NS      sss1.testrad.com.
testaccess.testrad.com.            NS      sss2.testrad.com.


;  End delegation