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.
From the InDesign Help File
QUOTE
Packaging a document or book for Adobe GoLive
During packaging, stories in an InDesign document are converted to XML files with an .incd filename extension. (Threaded text frames in InDesign are saved in a single XML file.) Paragraph and character styles applied in InDesign are converted to their CSS (Cascading Style Sheet) equivalents in Adobe GoLive. (See Designing documents for use in Adobe GoLive.) Nonprinting objects and objects on hidden layers, unused master pages, or the pasteboard are not included in the package.
Placed images and graphics from an InDesign document can be converted to an optimized format, such as JPEG or GIF, for faster display on the Web. You can also save transformations (such as scaling or rotation) that you've applied to imported graphics in InDesign, so you don't have to recreate these effects in GoLive.
Note: GoLive cannot import native InDesign graphics, such as ellipses or other shapes created using InDesign's drawing tools. (See the Adobe GoLive CS documentation.)
To package a document for GoLive:
1. Choose File > Package for GoLive.
2. Specify a name and location for the package, and then click Package.
Note: If you are working with a GoLive site, it's best to save the GoLive package to the web-data\web-packages folder in the site project folder. For information about GoLive sites and site management, see the Adobe GoLive CS documentation.
3. In the General tab, select View Package Using and choose an application. (Deselect this option to create the package but not open it.)
4. For Encoding, select UTF8, UTF16, or Shift-JIS (for Japanese characters). Be sure the encoding on the package matches the encoding of your GoLive Web page.
5. Specify options on the Images tab. (See Setting optimized image options.)
Note: InDesign prompts you to relink any missing images. If you are unable to link to a source file, InDesign will include a low-resolution version of the image in the package.
6. Click Package.
Tip iconMetadata associated with your document is included in stories you package for GoLive. (See Adding metadata to documents.)
To package a book file for GoLive:
1. Create or open a book file. (See Adding documents to a book file.)
2. In the Book palette menu, choose Package > Book for GoLive.
3. Specify a name and location for the package, and click Package.
4. Specify options on the General and Images tabs as described in the previous procedure.
5. Click Package.
Note: When GoLive is selected for View Package Using, GoLive opens the first document in the book package automatically. You can then open other documents in the book package in GoLive. (See the Adobe GoLive CS documentation.)