you have to be able to open the picture in some photo
editor to resize it. Even the one that comes with windows,
or a 3rd party one, like photo shop, paint shop, picture
it, etc.
When you open the file in that application, you can find
the resize command. Re-size the picture, then save it back
to the same file name and location.
Try to resend it.
Usual sizes for graphic files are
800x600
1024x768
640x480
the smaller the numbers, the smaller the resulting
filesize, but the worse the resolution and quality of the
picture you send. IT's a compromise.
Jpg files are the best choice to move files for email,
websites, etc.
hope that helps.
gmw