Google's new image search design is really nice, but if you miss the old search function, the Google Operating System blog shows off a quick way to return to the old view. At the bottom of the search screen you'll find a “Switch to basic version” link. Unfortunately, with Google's infinite scrolling this is hard to get to.
From the image search screen, type the End key on your keyboard (Fn+Right Arrow on Mac), and you're taken to the bottom of the screen. From here, click the “Switch to basic version” link and you'll get the old paginated image search back. Google doesn't save your choice, but if you prefer to click through results instead of infinite scrolling this doesn't take long.