one thing to bare in mind about the 1D is that the RAW files are .tif and not .cr2
not sure if its still the case but Windows Vista would corrupt the old .tif files
also you can get 3rd party batteries for about one sixth of the price of a Canon one and they will last about twice as long as the Canon ones. I've used them in my old 1D and my 1D mkII
One last thing, the colour reproduction on the 1D is nowhere near as good as cameras that are 4 years old, that was the first thing I noticed when I upgraded from my 1D to my 1D mkII