Hi!
And therein lies the rub (The "dirty little secret") - Based on what you're saying (and was said at the SlySoft forum), the .ISO image file that's been created in that fashion is incomplete - and can only be used in conjunction with SlySoft's program. My guess would be that, perhaps other than the more knowledgable users, there may likely be a good number who are unaware of the less-than-complete nature of the.ISO image files they've created. Good luck to them, I guess, should they ever transfer these .ISO image files to a system that doesn't have the requisite software installed - or if their demo version of the software expires and they're not in a position to afford the purchase price...As for the why you cannot open them with another program or play them is because of the AACS protection, the VID that cannot be copied and does not exist on the ISO.
And in order for you to play or do anything with ISO you need that VID to decrypt the Disk.
All Anydvd has is a database, that has a hash of a file that is always different for each move and it has it stored inside the programs and that is how it can open the ISO that are made.