shallow - 11:37 pm on May 15, 2011 (gmt 0)
Thank you ergophobe. Discussed the situation with my web developer today and he's going to try CSS Sprites, and a couple of other things to speed up the site.
If these work, they are much preferable to over compressing images and the resulting loss of quality visually.
I don't thoroughly understand CCS sprites, but they sound a little like image slicing I did years ago in Photoshop when I first published my site with FrontPage.