Here's a detailed example of how to create valid IFO files for the movie 'Final Fantasy disc1'. You can see the usage only from the first VOB file. Other files are just the same. You will need to download IfoEdit.
Below you can see our VOB file. It's just one:
Start IfoEdit, and press the button Create IFOs:
You will be prompted for the VOB file, you want to create the IFO files for. So specify our VOB file:
Now you will be prompted for a destination directory for the output IFO files. Take the same directory, and just press Save:
IfoEdit now scans the VOB file and collects all IFO-releated information:
After it has finished collecting all needed information from the VOB files, it creates two new IFO files:
Now you need to do some little modifications. Click on VTS_01_0.IFO, and you will notice that the audio and subpicture attributes are not correct:
The channels of the AC-3 audio streams are all set to 1ch. You need to edit this. Go into the table VTSI_MAT and scroll down to the audio VTSTT attributes:
The Audio stream 1 and 2 have 6 channels, and the other have 2 channels. Double click the Aud_1 attributes and change the second hex-value to 05:
Repeat the same for the second audio attribute. For the 3.rd, 4.th and 5.th, we will put the value 01 in there:
If you now go back to the VTS_Overview, you will see our audio attributes are now correct:
Save now your IFO file, and enjoy your movie.