Usually pictures including people does not make for good desktop wallpaper, one Exception is images of your beloved one, which do not make sense to share, and another exception is images of scantily clad celebrities, which is some circles may be popular but in others are highly controversial. But as a photographer I prefer to take photos with people, those pictures have more soul. Still, how such pictures can be turned in generally usable wallpapers? Make sure people are not recognizable, turn them in silhouettes, is a perfectly cromulent way.