If I understand the question, you'd simply build your Joomla site in the root directory, ie: www.doggeekz.com and when complete, delete your existing index.htm page and the joomla index.php file will take over.

OR, if you want to keep your existing site active whilst you (re)build it in Joomla, install the joomla files into a subfolder (eg: doggeekz.com/cms/) and then put in a htaccess redirect line to point to the new directory.