I need help organizing my files for poser 7. I don't know how to create new files and delete old ones. Currently I have the files just sitting in they're category slots, the defaults when you upload them to poser. I want to arrange all my content by people, animals, clothing, and so on.
could someone please show me how to do this?

If I understand your question, you are interested in creating external runtime folders other than the runtime folder provided by Poser 7.  Here is a link which should explain how to approach the organization:
http://www.silverblades-suitcase.com/tutorials/htm/20.html

Yes, this is what I was after. However, I can't seem to delete the files that are already there.
I can delete the content in them but not the file itself.

Also, the link did not tell me how to get each individual folder into poser 7.

Here is another tutorial link which actually explains things a little better.  It is based on Poser 6 but the concept is basically the same.  Caution - Do not delete any folders created by Poser 7 in the runtime folder.  These are essential and is the point of reference for the program.  Also, some base models and character morph sets need to be in the core runtime to work properly.  However, your downloaded content can be individually removed either deleting the folders themselves or using DAZ uninstallers if provided.

http://www.daz3d.com/i/tutorial/tutorial?id=1597&_m=d