I found two major drawbacks on your website.
1) it takes lots of time to load, i got bored and came back
2) I checked it on lowest resolution (800*600) and it showed a very wide horizontal bar.....................
The horizontal bar is the the same length on every resolution- unless you mean the horizontal "scroll" bar.
The speed of the page loading is pretty quick on mine, so perhaps you have a slow connection. The map will be the slowest part to load, but unfortunately, there isn't much I can do about that, as it is a large image!