If you want a link that doesn't automatically start downloading a .exe:
http://www.snapfiles.com/get/pictureresizer.html
Edit: Looking at the developer's site (
http://www.rw-designer.com/picture-resize), there are tons of commands that can be performed. Poking around, there's one for overwriting original files. Instead of using 'PhotoResize1024', use 'PhotoResize1024I', and the file names will stay the same. It'd also be a good idea to create a backup before doing it that way unless you absolutely don't want a copy of the larger files.