Pages Widget Can I have no Title?

You can modify this directly in the core of WP. Just go the /wp-includes directory and open default-widgets.php

On line 25 you will find the function related to this default WP plugin. Make your changes there save and upload to your server.

Default code:

$title = apply_filters('widget_title', empty( $instance['title'] ) ? __( 'Pages' ) : $instance['title'], $instance, $this->id_base);

Change to this:

$title = apply_filters('widget_title', empty( $instance['title'] ) ? __( '' ) : $instance['title'], $instance, $this->id_base);

This should do the job.