When you view thes photos from the disc, are you using software that came with the disc? Do you have to "run" the disc in order to view the pictures?
Or are you using some other viewer program, like Internet Explorer, or Imaging for Windows, or a third party program like Photoshop or ACDSee?
The original resolution of the picture, versus how it gets resized and saved for sending can be miles apart in quality. More information is needed....