Hi Russel.First, be sure you have only used .jpg for photos and gradients. Everything else should be .gifs.
The good news is that if all your new .jpgs are residing in the same folder you can import them into your web at the same time. As you select them, keep Control depressed.
The bad news is that you will need to insert them into the pages one-by-one. Don't use absolute positioning! Don't forget to delete the old graphics from your web.
The hotspots will need to be redone. Thumbnails will no longer be pointing to the correct file if the larger pics were replaced or renamed.
Sounds like you've got something to keep you busy for a while.

Sandy
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