Susan, I agree that the redesign is great, and also that the thumbnails are too small. I don't use Frontpage (or any MS products unless I have to), but I did a quick seach. I don't know you're experience level, or how Frontpage does it's versioning, but I found this:

To create a thumbnail of any image (pictures or clip art), simply select the image and press
Ctrl-T. FrontPage creates a second, 100-pixel-wide copy of your image. Obviously, this image has lots less detail than the original, and so it has fewer bytes and a smaller file size. And as we know, a smaller image makes for a faster-loading page.

You can change the size of a thumbnail (and its file size, as well) by right-clicking it, choosing Picture Properties, selecting the Appearance tab, clicking the Specify Size option, and entering a new value for the Width or Height option. When you save the page, FrontPage will prompt you to save this smaller image in your web.
But what if the default size is too small, or you don't like the border. It's easy to change the default options.

First, click Tools, Page Options, then select the AutoThumbnail tab. Here, you can change the default size of your thumbnails by
setting the height or width changing the thickness of the blue border around the image (or getting rid of it) giving the thumbnail a beveled edge, which makes it look more like a button.

If you change the default size, the resulting larger thumbnail may not be so pixelated? They do say the file size is larger which is a clue...

I'm sorry I can't help more... I do thumbnails the old fasioned way by vreating them manually in a graphics editor...

Great site and good luck with it!