First thing I notice is that you're using the deprecated "<?" short tags. Change all "<?" to "<?php" in your PHP scripts.
As for the startup error, it sounds like a required DLL couldn't be loaded. Take a look at this manual page: [man]oci8.requirements[/man]. Especially note the first sentence: "You will need the Oracle client libraries to use this extension. Windows users will need libraries with version at least 10 to use the php_oci8.dll."