OK, here are instructions on how to remux the fixed audio that even my grandma could follow:
You'll need:
Deamon tools, TS muxer, ImgBurn (all are free)
Mount the original ISO with Deamon Tools (or something similar) and go to "My Computer." Right click the virtual BD disk called "ROTJ_PDE" and choose "Open". Go to "BDMV\STREAM" and you should see a file named "00000.m2ts".
Open tsMuxeR GUI and drag the "00000.m2ts" file into it.
In the column "Tracks" uncheck the 1st audio file (track 2).
Unrar the fixed audio (pass: harmy) and drag it to TS muxer too.
Highlight the new sound (track 5) and choose English in the column "Language" Then press "up" 3 times until the new audio is track 2.
In the column "output" choose "AVCHD disk" and hit "Start muxing".
When the muxing's finished, you'll end up with two folders: "BDMV" and "CERTIFICATE." You can burn them with ImgBurn. Here are detailed instructions on how to do that:
http://www.afterdawn.com/guides/archive/burn_avchd_with_imgburn.cfm