Make a demo, and perhaps we can help. We can't guess exactly what
you did. Posting a couple of lines of code out of context doesn't
help much.
Global options should be set in code like:
$(document).on('mobileinit',
function() {
// set options here
});
This needs to be done after you load jQuery, and before you load
jQuery Mobile.
Disabling Ajax is absolutely the wrong thing to do - it throws the
baby out with the bathwater. (Disables one of the most important
features of JQM.)