Creating widget for page menu with images in header

Hello, I need to create a custom navigation using images, so after much searching I have learned that i can do this by creating a widget, which I have done, in the header area. I have the images in my images folder. As far as I can see the area has been created ok, a long rectangle box has appeared that spans the width of the header, although it is not very tall. I have tried to put links to the images inside the widget but cannot get any of the images to appear, can anyone help point me in the right direction, the link is http://heartattak.co.uk