I personally prefer to design to a max-width of 800px.
However, Im not so sure about a 1064 width? This is rather odd, are you sure this is correct, most monitors now display at 1024x768 or above. So I would recommend setting your maximum width to either 1024px or something around the 960px mark.
Generally I would say do what you feel is sensible, but as you are designing a regional tourist board website, it would be best to stick to guidelines set down by the W3C and WASP. It is definately worth reading
this article on web accessibility and it implications (under UK Law).
Btw. the beta version of the BBC site is now live if you are still using the old URL.
