The good people at Sucuri Security created an easy way to fix your WordPress site if it has been hacked. Just upload this file, after you change the extention from .txt to .php. You can do this through your hosting companies dashboard, or via FTP.
Then you just call for the script via a browser like this http://www.yoursitename.com/wordpress-fix_php.php
It seems to fix every hacked website I’ve come across?