Automator in Snow Leopard - Newbie MacBook Pro Owner Needs Help

All,

I'm new to Macs and am having a devil of a time figuring out Automator. I am trying to use an Automator script to open my library of photos and save them as JPEGs. I am using a "Save for Web" automator script I downloaded from Apple.com; it's supposed to open files and save them as JPEGs.

I can get the script to run on a single file or multiple selected files, but not on folders. I want to be able to select my entire pictures library and run the script against all of it, at one time.

I'm trying to create a Service. I have it set for "Service receives selected files or folders in Finder." Shouldn't this allow me to run the script against a folder and have it affect all sub-folders and files? If I pick my "Pictures" folder in Finder, and then click Finder - Services, it says "No Services Apply."

I'm sure I'm missing something obvious here; can someone point me in the right direction?

Thanks in advance,

Scott