Sorry, I haven't used it. Just looked at the demo and it sure has many features. I'm wondering if it has too many features. It would be trivial to loop through a table of email subscribers and send an email to them. Is this newsletter list fairly static? Will it change frequently? Do you want to get subscribers from your Website (via form?) If you only need to send a newsletter in HTML format (you mentioned images,) just loop through rows in a query and mail your message to them (you can paste it into a textarea in your form.) The Manual has everything you'll need to know to send an email in PHP (and an example shows how to send HTML.) The Manual also demostrates how to loop through a MySQL recordset.
As for the images, I suggest you create the newsletter message as a page on your Website. Use absolute URLS for your image links so you do not have to attach images to your emails (a bit too much overhead. Especially when/if your list grows.) You can copy the html (view source) on that page and paste it into the textarea of the form you will use to send the emails from.
