As the others have mentioned, this will never produce the desired result for email marketing. I think John covered this but HTML email is a unique animal all by itself - it can challenge even the most seasoned web developer because you have to deal with different email clients and not browsers - email clients are far tricker to code for. You need to use tables, inline CSS and ensure the code is as clean as can be. Dreamweaver (or other HTML coder) is definitely the way to go - forget InDesign and instead use Photoshop for the images.
Peter's suggestion of Mail Chimp is a good one as they have a huge amount of ready made templates that have been tested in all these email clients - you just add the images and content. If you want to go it your own way, this would be a good place to start: http://htmlemailboilerplate.com/
For reference you can also check out: http://24ways.org/2009/rock-solid-html-emails/. If you do decide to do this, I would then travel over to the Dreamweaver forum and ask any further questions there.
Sorry. I'm sure this is not the answer you wanted.
Rik