cropping photos - image editor?

I have a bunch of screenshots that I need to crop. I need to crop them all in the same way to show the same portion of the screen.

Currently the way I do this is boot into Windows and fire up Photoshop. I load all the files into layers, crop the document, and then export all the layers as files. Photoshop has tools built-in to make this pretty easy, but I'd be just as happy to stay in OS X and do my cropping there.

Is there a cheap (or free) piece of software that can do this? The key thing is that it's got to be easy. I don't want to manually load and place each image, and I don't want to manually save each layer and name it. I'd also like to stay under $50 if possible.

 

don't think i explained myself well...

I'm aware Preview and iPhoto can crop, but I want to crop hundreds of photos in the exact same way (say 2 inches from the top, 2 inches from the left, and 3 inches x 5 inches). I can do this one photo at a time in iPhoto or Preview, but I don't think I can do a batch in a single pass (which I can in Photoshop).