Is your torrent an ISO, or a VIDEO_TS folder? If the latter, you'll have to convert to ISO using ImgTool Classic.
A tool such as ppf-o-matic will compare the ISO of your old disc, and the ISO of the corrected disc, and produce a patch file. This file can then be distributed to anyone who wants to patch their disc.
That's the theory anyway; I've applied ppf patches a few times but I've never created them myself.
EDIT: link
Edit again - found new link