Help needed. “Image not supported”

So I have an image of a character that I'd like to print, using Adobe readers graph style, to make into a stand alone cutout. I've been trying to get adobe reader to take the image and let me print but it won't support the file. I've tried saving the image as a png and as a jpeg- neither work. What file type should I make it into? I have these choices: png, gif, jpeg, or single file HTML