Office Image Extraction Wizard is a simple application for extracting images from Office and many other document types (although not PDF).
Supported formats include Office 97-2003 (.doc, .ppt etc), Office 2007+ (docx, pptx etc), OpenOffice (odt, ods etc), NeoOffice (sxw, sxc etc), Apple iWorks (.pages, .template), chm, epub, fb2, cbz, dwxf, swf and more. Unlike some of the more basic competition, it doesn't need Office or any other libraries to be installed.
The program comes in the form of a wizard, keeping operations very simple. Choose "Batch Mode" and you're prompted to add your source files, select an output folder, and that's about it. Click "Start", your documents are parsed and any images saved in just a few seconds.
There is a little more flexibility in a few places, for those who need it. Your images can be saved to the same folder as source file, for instance; or to a new folder for each document; or to a single common folder for everyone.
This all worked well for us, with the program correctly extracting and saving JPG and PNG images.
The only small issue was that the images were sometimes given null timestamps (that's a date of 1/1/1980 00:00). It's not a major problem - if you're immediately importing them somewhere else it might not matter at all - but we'd have expected all images to have a timestamp taken from the source document.
It really needs PDF support, but Office Image Extraction Wizard works well and handles enough source file formats to be useful.