I have never really used them, but the process would be something like this:
Open one of the files.
On the actions panel (which you may have to turn on) press the New action button at the bottom.
Name it "Scale Down" or something, and press Record.
Now go the Image > Image Size menu and scale it down by the amount that you want them all to be scaled down.
Press Stop Recording on the actions panel.
Now you can close that file and don't save.
To automate the process for a whole directory of images now, go to File > Automate > Batch.
Select the action that you recorded, the source folder that your images are in, and a destination folder to put the scaled down ones in.
Now if you press ok it should go through them all, saving them. You'll probably be saving them as JPGs, so the quality slider will show up on each save operation, just press ok for each one. You can probably stop that somehow, but I haven't used actions much.
Open one of the files.
On the actions panel (which you may have to turn on) press the New action button at the bottom.
Name it "Scale Down" or something, and press Record.
Now go the Image > Image Size menu and scale it down by the amount that you want them all to be scaled down.
Press Stop Recording on the actions panel.
Now you can close that file and don't save.
To automate the process for a whole directory of images now, go to File > Automate > Batch.
Select the action that you recorded, the source folder that your images are in, and a destination folder to put the scaled down ones in.
Now if you press ok it should go through them all, saving them. You'll probably be saving them as JPGs, so the quality slider will show up on each save operation, just press ok for each one. You can probably stop that somehow, but I haven't used actions much.