Photo editing software to cut part of one image and paste into another image?

What photo editing software allows the user to cut part of one image and paste into another image? Several years ago I used Photo Deluxe which allowed such editing with ease. For example, a friend had some photos where she and her husband were in one picture and her son was in another picture. Both photos were taken at the same event, but she wanted one photo with her family together. I used Photo Deluxe and cut and pasted her son into the other photo (with a little resizing and cleaning up) with great results. Sadly, Photo Deluxe is no longer produced and does not work with Windows 7. I can no longer "resurrect" my old computer for photo editing.