There seems to be a bit of a problem with the menu. The selection doesn't move smoothly when you hover over one item and them move down to hover over another one.

It takes too long for it to unhighlight the current item and then it feels like their is a pause before it highlights the new item. It also somethings highlights one of the intermediate items on the way. The result of this is you end up waiting for the UI to catch up with you so you can see the sub menu.

You could make the HTML quite a bit more compact if you made more use of CSS classes. There is lots of formatting data which should be using classes instead.

You should also move your inline Javascript into separate .js files, so that it can get cached sensibly on the client.

Both of these will significantly reduce the size of some of the pages, some of which are a little large. There are some "short" pages that are 135kb or so in size, which would take 30 seconds to download on the average modem.