Hullo Ev'ry Bardy!
Here is the simple technical answer to the problem.
If the problem exists in one browser and not another, then the problem is with the browser and not the web site!
Simple eh? Diane and David have nothing to do with it.
Martin does not mention which version of IE he is using which is not terribly helpful. I doubt that he is using IE6x which were dreadful. IE 8 has it's problems. IE 9 seems to be pretty stable and standards compliant which means that there are virtually no problems with it when visiting web sites. That said there are occasion "Issues". Click the compatibility view icon in the address bar, press F5 and see if that fixes it. If not, then go to ToolsManage Add ons and disable anything not Microsoft (just for testing purposes). See if the problem persists.
Update Java
Update Flash
Update Shockwave
Update Windows.
Have fun and remember what Dr. Johnson said: " sir, I have read your book and it is both good and original. The problem is that the parts that are original are not good and the parts that are good are not original".