Remove a custom options name/value pair

based on MMK’s help below, here’s the code:

$toremove = 605 // I actually use a var like so $toremove = $_REQUEST['somevar']; I'm just using 605 as an example
$selectid = get_option('swcs_postpage_id');
$key = array_search ($toremove, $selectid);
unset($selectid[$key]);
update_option(swcs_postpage_id, $selectid);