You will need to use a photo editing program for resizing if you want to have decent results. You can use that program for adding the border too.
You could go to a professional photographer and say you want a picture for a passport. They will take a picture and print it to the right size.
Thanks everyone. I forgot a convenient feature of PowerPoint: the ability to save objects as native images. In other words, that new image, with the rectangle border around the original photo image is itself savable as JPG. I think all I have to do now is tell the photo people that I DO want the border to print. The effect, therefore, is to "shrink" the image, including the head.
THe question remains: when I copy an image from PowerPoint into Paint, the image deteriorates markedly. What's going on? Thanks.