Reduce iWeb site

Hello,

I have a rather large site of teaching materials which I've created in iWeb.
Basically worksheets and images for teachers to use for teaching English.
Over the past year I've done some things to make it lighter, like reducing image sizes before posting, reducing PDFs on the site, and getting rid of excess drop shadows and reflections.

I'm wondering if anyone has advice or ideas on how to reduce it further. It seems to load slowly on some browsers such as IE.

The site is: www.myenglishimages.com

I do some freelance illustration but I'm not a web designer (thus the reason I'm using iWeb.)

Thanks a lot for reading this and any feedback or links to older posts I haven't seen!

M