Changing pics to homepag

I am having a little trouble changing the pics on my homepage. I can upload and delete with no problem but when I do upload a pic it is either very small or blurry. Do I need to be looking for a specific dimension or pixels or what with the pics? Or is there a setting I need to be changing to get it to that panoramic kind of view? Any help I can get would be great!

Not sure if this helps, but I cropped all the pics in my rotator to 960x280 and they fit perfectly.  As long as your original picture file is at least that big, you shouldn't be seeing any stretching or scrunching, pixelation, etc.