If I had to pick between a black robe a blazingly orange face I'd go with the black robe, although I'm not sure why you'd have to choose between the two. It looks like he's been spray painted.

This is how Obi Wan appeared in the original theatrical run:

http://savestarwars.com/images/senatorcorrected/technicolor15.jpg

http://savestarwars.com/images/senatorcorrected/technicolor8.jpg

Very, very natural flesh tone. On the pale side, if anything.

I jst watched the Lightsaber fight again:

http://www.youtube.com/watch?v=pXQdAsqKgw0

Obi is NOT too orange. He may look a bit orange in that one pic but not in the overall clip I saw.