I'm often batch processing files in Photoshop 7 and have found that Photoshop will process files faster if you click on the desktop after initiating the automated batch process.
While the Finder is the foreground app, Photoshop doesn't bother with screen redraws as it opens and processes files. This can be a real time saver for processing large numbers of files.
You should also select 'Accelerated' from the Playback Options in the Actions pallette.
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