by Ken Task.
Anytime I've had similar issues, it was related to either permissions on the config.php file or an in-correct value in config.php (not bad enough to deny access, but just mess up the way it rendered).
Maybe it's time to disclose more information about system:
Operating system is? Remotely hosted or not? If remotely hosted, who is provider? Anything additional running in PHP (Zend/suPHP/?)? Anything additional in Apache (apc, etc.)? PHP and MySQL versions, etc.
How was Moodle installed?
Turning on Debug shows no errors?
'spirit of sharing', Ken