How would I get my wordpress blog that I just installed to show up on the main page of my website?
There are few ways to achieve that.
If you already install wordpress in a subdirectory, you can redirect to wordpress from your index file. Create a index file in the home folder of you domain like this:
OR just create a file called index.php with one line in it as follows…<?php header('Location: http://photos.theMezz.com'); ?>
put that in your main dir and replace Location with the URL to your blog
The other option would be to move the whole blog out of the folder it is in and move to the main page. This would break the one click install if you used it though preventing upgrades using one-click.
the other option may be to change the folder the domain points to to be the one containing the blog
Both these would require a few changes to the wordpress install because of the change to the url it will be using.
take a look at http://codex.wordpress.org/Moving_WordPress. The instructions are for various ways to move wordpress.