What about a smaller image when clicked opens the original larger image?
But to reduce the size:
MS Photo Editor - Open you picture and click, Image, Resize. Put in your dimensions and you'll see the image smaller but as you can see it does not look good.
Paint - As far as i know you cannot resize an image.
Serif PhotoPlus - (i have Version 6) Open your picture and click, image, image size and put in your dimensions. Again you'll see the image smaller but it looks terrible. You can push the sampling to High, this at the bottom. A little improvemnt but it still looks terrible.
Your using Frontpage arent you? Well Insert your picture into your page. Right click the pictre and choose, Picture properties. Put in your dimesions but from my little test just them, It still looks terrible.
With the above you'll have to experiment with your ownm images.
The best to last:
click here and you can resize an image and keep the qaulity that you want (to a point) Open your picture, image, resize/resample and have a play with the size thier. It's alot better than the above.
But the clicking a smaller picture to a larger picture i think is the best way.