If you are connecting to a remote MySQL server then it may not be accessible remotely. If you can you should attempt to run a local MySQL server to see if this will let you start working with the tools. On our product support pages under General Technotes we have a guide called Web Development: Before you Begin. It covers getting a local server including the MySQL setup.
One other thing that you may want to try is to make sure that DW is closed then go to the local root folder for your site and find the mmServerScripts folder and delete. When you launch Dreamweaver again and test your connection and recordset this should be recreated. It is possible that there is an error in here somewhere, if this is the problem deleting it and having DW recreate it should resolve the problem.
Let us know how it goes for you.
