WordPress Widget Confusion

<?php

    class signup_Widget extends WP_Widget {
        function signup_Widget() {

            $widget_ops = array(
                'classname' => 'widget',
                'description' => 'Email signup form.'
            );
            $this->WP_Widget( 'email-signup', 'Email Signup', $widget_ops );

        }
        function widget($args, $instance) {

            extract( $args );

            $title = apply_filters( 'widget_title', $instance['title'] );
            $script = $instance['script'];

            echo $before_widget;

            echo $before_title . $title . $after_title ;
            htmlspecialchars( $script );

            echo $after_widget;
        }

        function update( $new_instance, $old_instance ) {

            $instance = $old_instance;

            $instance['title'] = $new_instance['title'];
            $instance['script'] = $new_instance['script'];

            /* Exists to test output, unfortunately they show up with no data */
            file_put_contents( '/wp_results.txt', print_r( $old_instance, true ) );
            file_put_contents( '/wp_results.txt', print_r( $new_instance, true ), FILE_APPEND );

            return $instance;

        }

        function form( $instance ) {
            /* Defaults */
            $defaults = array(
                'title' => 'Email Signup',
                'script' => 'Default Email Signup Script goes here'
            );
            $instance = wp_parse_args( (array) $instance, $defaults );
            ?>

                <p>
                    <label for="<?php echo $this->get_field_id( 'title' ); ?>">Title:</label>
                    <input id="<?php echo $this->get_field_id( 'title' ); ?>" name="<?php echo $this->get_field_id( 'title' ); ?>" value="<?php echo $instance['title']; ?>" style="width:95%" />
                </p>

                <p>
                    <label for="<?php echo $this->get_field_id( 'script' ); ?>">Script:</label>
                    <input id="<?php $this->get_field_id( 'script' ); ?>" name="<?php $this->get_field_id( 'script' ); ?>" value="<?php echo $instance['script']; ?>" style="width:95%" />
                </p>

            <?php
        }
    }
    register_widget( 'signup_Widget' );

?>