I've never worked extensively with photos, but I don't think AppleWorks will handle them. Download JpegViewer for looking at jpeg files.
Easy Open and Dataviz are not related. Dataviz is the company that developed MacLink Plus file translation software. If you don't have MLP on the machine, none of the Dataviz stuff is being used. To further reassure yourself, create a folder somewhere outside of the System Folder, and move all the stuff you want to trash into it. (Command-Y will put it back where it came from later, if necessary.) Do the stuff you want to be able to do, and if you have no problems, take those things off the computer. If you're still unsure, copy them onto a disk first.