Checkout using Reach Theme

You can remove fields with a simple bit of code. See https://github.com/Charitable/library/blob/master/donation-form/remove-donation-form-fields.php for an example of how to remove a field. Read the comments at the top for the keys to use with the other fields.

There are a couple ways to actually add this code to your site. See https://github.com/Charitable/library#how-to-use-the-code-snippets

Cheers,
Eric