I need to create pdfs that have editable fields but want to secure the clipart in the file. How do I designate certain sections as editable and others as secure?

You can apply a security policy that allows filling in form fields but prevents the extraction of content from the file. However, keep in mind that this is a far from 100% secure solution. There are many ways around such a policy, the easiest of which is simply to take a screenshot of the page and then paste it in a graphics editor to get a copy of your artwork...