Hello Linda,
Always use Insert, Picture, From File, click the image, and choose Insert.
If you copied and pasted images and are using version 2003, for each image or
picture, cut it, then choose Edit, paste special as .gif or .jpg (for
photos). This will reduce the file size a great deal.
Include a complete blank slide as the first slide in your presentation.
This blank slide will function as the file preview, the image PowerPoint
displays when you select a file in the Open dialog box with a preview option.
The new preview image of the blank slide is much less complicated than an
actual slide preview, and this too may reduce the file size of your
presentation.
Cheers,
Annie