Adding Fields to Order Form

[Guest]

Hi,

 

I'd like to add an additional drop down menu and another text field to the order form. I have searched the forum, and one post I read (for DELETING the comments box) said to edit the following files:

 

- /catalog/checkout_shipping.php

- /catalog/checkout_payment.php

- /catalog/checkout_confirmation.php

- /catalog/checkout_process.php

- /catalog/includes/classes/order.php

 

My questions are:

1. Are these the same files I should edit to add my new fields?

2. Can I add the fields in HTML?

 

Thanks for any help.