Removing header space

Currently, I have a YouTube video in the header of our site. I want to remove this YouTube video to put in a better slideshow that I created with the MetaSlider Plugin, however I don’t know how to get that slideshow in the same place as the YouTube Video. If I delete the YouTube Video and leave the header image blank, there is a bunch of black blank space before scrolling down to see the “Welcome” message. Is there any way to put a slideshow in the header space, or remove the blank header space so that once the YouTube video is removed, the “Welcome” message will be at the top of the page? (Then I could put the MetaSlider slideshow right under where it says “Welcome”)

The page I need help with: [log in to see the link]