Two questions in one - Making my page slightly wider and what could make my site slow

Hi Everyone

I haven't really played with my site for a while so out of practise.
Can anyone please tell me how to make my site a bit wider, I like the background so don't want the page and column to take up the whole site.

Plus also, my site is slow loading which isn't really a huge problem as it is normally only visited by family and friends but is there a way for me to tell what is causing the slow downloading, is it purely the photos on there?

My website is www.chocolatebones.co.uk

Thanks for any help

Kev