Um, that's not CS3 you have there, SB. That must be either CS1 or CS2, 'cuz CS3 has the following options:
Package (this is for commercial printing only)
Cross-media Export - XHTML/Dreamweaver, XHTML/Digital Editions (e-books) and XML.
From Adobe CS3 Help:
QUOTE
Export content as XHTML
Exporting to XHTML is an easy way to get your InDesign contents into web-ready form. When you export contents to XHTML, you can control how images are exported, but the formatting of text is not preserved. However, InDesign preserves the names of paragraph, character, object, table, and cell styles applied to the exported contents by marking the XHTML contents with CSS style classes of the same name. Using a CSS-capable HTML editor, such as Adobe Dreamweaver or Adobe GoLive, you can quickly apply formatting and layout to the contents.
What gets exported
InDesign exports all stories, linked and embedded graphics, SWF movie files, footnotes, text variables (as text), bulleted and numbered lists, and hyperlinks that jump to text. Tables are also exported, but certain formatting, such as table and cell strokes, is not exported.
What doesn’t get exported
InDesign does not export objects you draw (such as rectangles, ovals, and polygons), movie files (except for SWF), hyperlinks (except for those that jump to text), pasted objects (including pasted Illustrator images), text converted to outlines, XML tags, books, bookmarks, SING glyphlets, index markers, objects on the pasteboard that aren’t selected and don’t touch the page, or master page items (unless they’re overridden or selected before export).
Reading order
InDesign determines the reading order of page objects by scanning left to right and top to bottom. In some instances, especially in complex, multi-column documents, the design elements may not appear in the desired reading order. Use Dreamweaver (or another HTML editor) to rearrange and format the contents.
Before you export, you may want to influence the reading order by grouping related objects. Objects grouped in InDesign are also grouped in XHTML.
If you’re not exporting the entire document, select the text frames, range of text, table cells, or graphics you want to export.
Choose File > Cross-media Export > XHTML / Dreamweaver.
Specify the name and location of the HTML document, and then click Save.
In the XHTML Export Options dialog box, specify the desired options in the General, Images, and Advanced areas, and then click OK.
A document with the specified name and an .html extension (such as “newsletter.html”) is created; if specified, a web images subfolder (such as “newsletter web images”) is saved in the same location.