Tim Grey, author of Photoshop CS2: The Digital Photographers Guide, offers two free actions you can use to automate repetitive tasks in your photo optimizing workflow.  Download Tim Grey Workflow.atn from Tim's website. To install these actions in Photoshop CS2: drag that .atn file to the Presets>Photoshop Actions folder inside the Photoshop CS2 application folder. In Photoshop, open the Actions palette from the Window menu at the top of the screen. Click the arrow at the top right of the Actions palette and choose Load Actions from the palette menu. Select Tim Grey Workflow.atn and click Load.

In the Actions palette, click the arrow to the left of Tim Grey Workflow to reveal two actions. The first action creates a Levels adjustment layer, a Color Balance adjustment layer, and a Hue/Saturation adjustment layer, pausing at each to allow you to insert settings appropriate for the photo you're working on. It also creates a blank layer for use with the Clone Stamp or Healing Brush tools so that corrections made with those tools are isolated on a separate layer. And it makes a special Dodge & Burn layer filled with neutral grey. You can lighten and darken areas of a photo by painting with white and black at lowered opacity on that Dodge & Burn layer. The second action does the same thing, but helps you along by including instructions that appear as the action plays.
More on these actions after the jump.

You can play either action on a single photo by opening the photo, selecting the action in the Actions palette, and clicking the Play button at the bottom of that palette. To play them on multiple photos, choose File>Automate>Batch. Set the options in the Batch dialog box and click OK to play the action on a folder full of photos.