Hmm, I don't know why vBulletin does call compile_template() on phpinclude_start as there should be nothing to do in this template ...
Anyway, try to remove
PHP Code:
// Example of how to include a separate file:
// ob_start();
// require("yourheader.html");
// $header = ob_get_contents();
// ob_end_clean();
I couldn't test the banner & statistics stuff as I don't have the files, but the greeting seems to work then.