It could be that the resolution of the image, would not display well at any other size other than small. The actual size, is probably "small"
Try with a picture that came from a camera, to see what options you get.
Thank you for your prompt response.
I just took a photo and imported it from the camera into iPhoto.
I then printed it at 6"X4" and scanned it to Documents.
The iPhoto version resized nicely as an attachment into small 28KB; medium 69KB; large 225KB and actual 1.9MB.
I then attached the scanned version which had poor image quality and the attaachment was small 35KB; medium and large 55 KB and actual 1.1 MB.
It would seem that the issue lies in using a scanned image so I will talk to Epson.
Thanks again for your guidance