I'd take the 5D2...the 1D4 will be bulky and will add to the weight. For lenses, maybe something in the 24-70 and a 70-200 range. 24mm on a 5D2 is still pretty wide, and a 70-200 will allow you to compress images for a different look if you happen to be shooting from the rim. If you need wider than 24mm, an option would be to stitch multiple frames. As far as batteries, plan on 1 battery per day, with maybe one extra, for a total of four. The LP-E6 battery holds a charge really well...give them a good charge the evening before you head out and you should be good. If you use Live View a lot, this will drain the battery more quickly which is where the extra battery will help out. I recently shot for three days at Monument Valley and only used two out of the four batteries that I brought along.
As far as accessories goes...tripod, polarizing filter for each lens, and maybe a graduated filter or two.