One of the neat things about OpenOffice is the many extensions available. Oracle has a PDF import extension for OpenOffice Draw, which can import just about any unsecured PDF document.

Download link: http://extensions.services.openoffice.org/project/pdfimport?intcmp=1549

This allows you to open PDF documents directly from the menu. There are still a few quirks now and then, but they don't spoil the usefulness of the extension.