This is actually quite straightforward and it only takes a minute of your time. The first method is easy if you have a short Word document just a couple of images that you want to save. All you need to do is to right click the image in the document and select Save as Picture from the menu that is displayed.
This works on Word in Office 2013, but apparently there is not an option to save pictures in very old versions of Word. Try it and see.
The second method is to open the document in Word and then press the Prt Scr key. This copies the contents of the screen and saves it to the clipboard. You can then open a photo editor or paint program and paste it in. The free GIMP photo editor is great for this. Start GIMP, select Edit, Paste as new image, then use the rectangle select tool and Crop to selection on the Image menu. The picture can then be saved.
Saving images individually is slow and tedious for long documents with a large number of images. Taking screen shots is fiddly and time consuming too.
The best method is to save the Word document as a web page. Go to File, Save As, select Web Page in the Save as type list, and save it.
This saves the text as an HTML file and it also creates a folder and places all the images in it.
For some reason when I do this, it saves the images twice. Once as a .png file and once as a .gif. It is not a problem and both images are identical. You don't need the .gif images and they can be deleted. The .png file format is better.