DNS and Apache Troubleshooting

There are three parts to this job. Part 1. I have migrated my website to a virtual private server (Linux CentOS, MYSQL, PHP) and it is running ok. However I have my name servers (ns1 and ns2 )set up to point to the same IP which is not good practice. I purchased an account at DynDNS to add an extra name server but I get a warning that "One or more of the nameservers listed at the parent servers are not listed as NS records at your nameservers. The problem NS records are: ns2.mydyndns.org." So I need someone to fix that for me. Part 2. I have noticed when viewing the site that I see intermittent broken images. This has been happening for a few days ever since the migration. I have no idea whats causing this. Could be Apache, could be RAM, could be DN could be a router. I need someone to trouleshoot it for me. Part 3. I need someone to view the active services on my server to ensure that no services are running that are just hogging memory. I need to be advised if the current set up is ok or I need to implement further changes or get more memory etc.