You can grab a full copy of DPP, but you have to be inventive. I managed to find the serial number of a 1 series camera somewhere on the Internet. I also found a Canon Japanese site with a copy of DPP version 1 (full) that you could download if you had a valid 1 series serial number. Once you had the full version, install it, then grab the latest updaters. Voila. The Japanese link is:
http://web.canon.jp/imaging/sdl/dpp-e.html
I found the serial number for an original 1D on dpreview.com's review of the very same camera. I can't remember where, but from memory, there's an image of the base of the camera which has the serial number clearly visible.
But, there are easier ways. A quick google reveals this helpful page:
http://www.fredmiranda.com/forum/topic/597859
look for the post by corndog, he has a URL to a DPP download. Direct URL for download is:
http://files-upload.com/files/684917/dpp.rar
I can't guarantee that this file is safe or untampered with. If you want a copy of DPP, I have full CDs of DPP 3.0 from memory, I'm happy to either make an .iso out of it so you can download and burn, or burn a copy and post to you. PM me if you're interested.
Why not try RAW therapee instead?
http://www.rawtherapee.com/
Dave
edit: here's the dpreview image I was referring to:
http://a.img-dpreview.com/reviews/Ca...mages/base.jpg
further edit: mods I don't believe that this is endorsing piracy. The serial number is freely available on the Internet, and so is the link to the Japanese DPP site. Software is not being reverse engineered or pirate in any way by doing it this way.