Adobe Dreamweaver is the Macromedia Dreamweaver software that has been rebranded and enhanced with features such as interoperability with other Adobe software products.
Adobe Systems Inc. acquired Macromedia. The acquisition was closed on December 5, 2005. Since then, Adobe has selectively integrated Macromedia software brands and web development tools into its own brand name and logo.
What was formerly 'Macromedia Dreamweaver is now officially called 'Adobe Dreamweaver.'
So if you are evaluating a product that refers only to 'Macromedia Dreamweaver' without any Adobe logo on it, check the release date. You are probably looking at an older copy of the web development tool (release date of 2005 or earlier). Suggest that you research if the version that you are evaluating is supported anymore and whether or not it can be activated by a valid license key by Adobe.
When I check the manufacturer's website (see Adobe.com), Adobe Dreamweaver CS4 manufacturer's list pricing is a fraction of the price of Adobe Creative Suite 4. This is probably because Creative Suite 4 includes more integrated software programs in addition to Adobe Dreamweaver CS4. CS3 is an older software version than CS4.
All of above software work just fine for generating HTML-based website development.
If you need a tool for creating a Flash animated site, you will need a Flash development tool. Dreamweaver is not a Flash development tool.