The problem seems obvious – many JS errors – however what is causing them is not so obvious. There is a lot of JS on the page. Probably a case of a couple things that just don’t get along well together.
I would recommend keeping things a bit more simple to keep the page free of JS errors. However if you’d like help identifying the exact culprits I might (with a bit of time and effort) be able to help pinpoint it. You’ll need to send the file in question http://yourhead.com/support
However in cases like this where there are several scripts running side-by-side there is likely no real “fix” – other than simply removing one or the other.
If you’d like the more expedient approach, I’d recommend copying the page content to a new page – without all the extras – and then add in each of the extras you want – testing after each. When you find the thing that makes it die – remove that and stop.