get menu id using its name

You can use the function get_term_by and use ‘name’ in the field param.

<?php get_term_by( $field, $value, $taxonomy, $output, $filter ) ?> 

Example:

$term = get_term_by('name', 'Social Network', 'nav_menu');
$menu_id = $term->term_id;

Here is the link to the codex page:
http://codex.wordpress.org/Function_Reference/get_term_by

Hope this helps.