I wouldn't go delving into pages of code. This can probably be solved within the moodle application itself...
I don't understand what went wrong, but I tried logging in in several of your courses by typing in the url's
http://ww2.songwritersguild.com/php/moodle/course/view.php?id=2
http://ww2.songwritersguild.com/php/moodle/course/view.php?id=3 etc...
straight into IE's address bar and I got the message:
"Sorry no guest users allowed."
But (and I think this message shows that nothing really happened to your courses) I got shown the title of each course!
Maybe you can try logging in to one of your course in this way. If that works, you can be sure that the courses still exist. The only thing messed up is the site's homepage.
BTW Nice music