In the form builder wizard, you can edit the form design.
In the form design editor, select Form Elements from the first dropdown, then select Captcha from the second.
this page will allow you to configure the captcha settings.
Also in the form builder wizard, you can add form elements.
to alter the way the labels appear in the email, you could use a replace fiunction.
In the template the code to write the label looks like:
<?php echo(str_replace("_"," ",$pkey)); ?>:</th>
you can use the replace function to remove part of the form name from the label.
say the elements name is "Appointment_request_group_First_Name", and you want to only show "First_Name for the label:
<?php echo(str_replace("_"," ",str_replace("Appointment_request_group_", "", $pkey))); ?>:</th>