For your video sources, XBMC was changed so that it no longer automatically adds your drives, and you have to add them yourself if you want them. If you copied sources.xml from an old build into this one then it should work to give you all your old stuff, although I can't guarantee as I don't know all the changes made. If not just readd.
The widescreen is often seen as a common probalem, although its very simple (I was here asking about it a couple months ago, but nobody likes to answer if the answer is glaringly easy to find. The widescreen settings are not completely controlled by XBMC. They will only become available if widescreen is eneabled in the MSDash. You'll need to boot to it, enable widescreen on there, and then enabled it in XBMC settings.