You need to provided a URL, so that we can take a look for ourself. But I don't thing that's going to change things for you. There is nothing on your web site that can stop animated. But I believe that in Internet Explorer, under Internet Options --> Advanced, a user can stop their browsers from playing animations. This may also be part of the security level you have defined.
A URL might help us determine if there is really a problem.
My Internet Explorer must be faulty, as I used Firefox and found my animations to be working fine. Could someone tell me how I can delte this post, so as not clutter up the forum with solved problems? Thanks!