Editing info for podcast

Your feed doesn't have any of the 'itunes:...' tags which are necessary to carry the artwork, author and so on; nor the xmlns 'declaration' in the second line:

<rss xmlns:itunes="http://www.itunes.com/dtds/podcast-1.0.dtd" version="2.0">

which is necessary for iTunes to be able to read these tags.

This page includes a sample basic feed so that you can see what one should look like:

http://rfwilmut.net/pc

I don't know anything about how you are creating your feed. The 'generator' is listed as 'A-Infos Radio Project', so I don't know whether this is actually a program or service which creates the feed from info you enter into it, as many of these programs do: it's very often the case that you can't edit the feed. If you do have access to the feed you can edit it in any plain text editor, making sure that you retain the correct extension when you save; also remembering that you need to be very careful about accuracy - apparently insignficant errors can wreck it. My page mentions some of the errors you can fall into, and the Apple Tech Note I link to in it is worth studying for a detailed look at feed creation.