From the excellent forums on robgalbraith.com. A participant asked "Can you batch convert raw files in CS2?" and after some back and forth Thomas Knoll himself responded with the essential steps.
"If all you want to do is just convert a bunch of raw files and save them as TIFF, JPEG, or PSD (or DNG) file, it is very easy.
1. Select the raw files in Bridge that you want to convert, and pick "Open in Camera Raw" (Command/Control-R).
2. Adjust the raw conversion settings on the images you want convert, if you have not done so already.
3. Press the "Select All" button (or type Command/Control-A).
4. Press the "Save xxx Images..." button (xxx is the number of images selected") (or type Command/Control-S).
5. In the save dialog, specify the destination directory, the file naming rules, and the output format.
6. Exit the save dialog by pressing the "Save" button.
A background batch save queue is now running. The status is shown in a "hyperlink" above the buttons in the Camera Raw dialog. You can press on this hyperlink to see a detailed save status dialog.
You can exit the Camera Raw dialog and select the next batch of raw files. The background save queue will keep on running as long as Bridge is running."
Suggest you follow the entire thread here.