Changing to a New Domain Name

What I’m trying to do:
I’m in the process of switching my subdomain name, http://test.mattersoflifeanddata.com/wordpress, to a primary domain, http://www.mattersoflifeanddata.com
I’m not changing servers and I have the same IP address.

What I have:
My domain is hosted at Namecheap.com and my cloud server for my site is hosted at Rackspace. I have several different domain names redirecting to the primary domain I want (www.mattersoflifeanddata.com). The primary domain’s record type is listed as “A (Address)”. I’m working with MySQL Workbench to access the database, Linux to get to the files, and FileZilla to FTP.

My Problem:
My website is not rendering correctly after switching domain names on the wordpress Admin page. The homepage looks distorted and blown up with all the links going to a “Page Not Found”.

What I’ve already done:
I started out changing the ‘SiteURL’ and ‘Home’ to the desired domain name, which locked me out of the site, causing me not being able to Login to the Admin page. I’ve proceded to look at different Codex including… Changing The Site URL and Changing Your Domain Names and URLs I’ve followed the directions as well as looked into the different ways you can do this, but none have worked for me.

In my last desperate effort, I have gone through each table and each column on my wordpress database and have changed every instance that I saw the old domain name and have replaced it with the new domain name. Even with that, I’m getting the same distorted results.

I’ve been searching forums for days trying to find an answer to this problem. I’m not sure if this is an issue with my WordPress site, or a problem with where I have my domains hosted, but I decided to give it a shot and try to ask here first.

Does anyone have an idea of what I’m doing wrong? Or have had any similar experiences?