I think you’ve been hacked. Looking at the file 1.php in your web folder, it has this code:
And your index.php is FILLED with stuff like this:
submit = 'http://links.freedns.ddosattacker.com/links/api.php';
Please raise a ticket so we can scan the whole account, but also read http://wiki.dreamhost.com/WordPress_Hacks for how to clean your site.