If you want an application, Coffee Cup is not bad.
Otherwise, Joomla and Wordpress are great because they're free and you do all the editing through the browser. Although I used to use Dreamweaver commercially, it's nice not having to lug the "Dreamweaver PC" about when I want to do basic edits.
You could sign up for a free wordpress account at www.wordpress.com, and see how you get on.
If you're into learning HTML, try http://w3schools.com/
This is a great site for open source HTML editors, you might find something for your needs here too:
Good luck with the site :)
p.s. check out my hubpages and blog for some information on how to make your website more effective by making it user-friendly.