A quick glance and there's a few things. FIrstly, MX records should point to A records, not to IP addresses...
Code:
% nslookup -silent -type=mx brlewis.com 65.19.178.131
Server: 65.19.178.131
Address: 65.19.178.131#53
brlewis.com mail exchanger = 50 65.19.178.131.brlewis.com.
There are a couple of minor points you may not be aware of. The first is that since you have multiple entries for "@" they can all be collapsed into one.
The second is the CNAME for www. Because it's a CNAME you now also have MX records, NS records and SOA records for the "www" name etc etc
Code:
% nslookup -silent -type=mx www.brlewis.com 65.19.178.131
Server: 65.19.178.131
Address: 65.19.178.131#53
www.brlewis.com canonical name = brlewis.com.
brlewis.com mail exchanger = 50 65.19.178.131.brlewis.com.
It's just a minor point

What I would do is:
Code:
$TTL 1d
@ IN SOA ns1.brlewis.com. brlewis.alum.mit.edu (
2004061601 ; Serial (yyyymmddxx)
86400 ; Refresh (1 day)
7200 ; Retry (2 hours)
604800 ; Expire (7 days)
86400 ) ; Minimum (1 day)
IN NS ns1.brlewis.com.
IN A 65.19.178.131
IN MX 50 mail.brlewis.com.
; We use the same IP address a lot, because we use different
; names for the same service. We could just have
; "linode.brlewis.com" as the one name, but...
www IN A 65.19.178.131
ns1 IN A 65.19.178.131
ns2 IN A 65.19.178.131
mail IN A 65.19.178.131
Note that the same IP address is used in lots of places now. As the comment says, we _could_ reduce it and just have it twice (an A record for the @ line, and an A record for a general line (eg "linode") and have everything (NS, MX,WWW) all point to that. That's just a matter of taste
