Try also clicking on the compatibility option of that bloody browser and if it gets stuck just place a msg about it or use the rendering option Jason suggested.
Im also detecting on the link you placed here a javascript error with the spry validation, maby that can be, it also took a while to load because the background is a very heavy picture and while it was loading on IE the fields where not responding.
Nice that your using bootstrap ill be writing soon here on webassist a tutorial on how to convert webassist form elements into bootstrap ones