How to secure insert statements in wordpress?

Solution:

You can easily use $wpdb->insert( $table, $data, $format ). Usage:

$wpdb->insert( 
'table', 
array( 
    'column1' => 'value1', 
    'column2' => 123 
), 
array( 
    '%s', 
    '%d' 
) 

);

More info in: http://codex.wordpress.org/Class_Reference/wpdb#INSERT_rows