Drop down menu issue with Internet Explorer

If you go to my site via Internet Explorer > go to Workplace Accident page (http://supplementalbenefits.org/workplace-plans/accident/) >then hover over one of the main menu headers, and you will notice that the ones with the longer drop-down menus drop behind the video window – thus hiding the other menu options.

When loaded in Firefox and Chrome, the drop-down menus fall right over the video window, so this is an issue solely with Internet Explorer. Any way to fix this with some code?

Many thanks!