Here is where most guides fail. Many CD-based games are distributed as (multiple tracks). If you simply convert game.chd to game.iso , you lose audio tracks (CD-DA) and mixed-mode data.
chdman extractcd -i "game.chd" -o "game.cue" -ob "game.bin" convert chd to iso better
The practical verification: Mount the new ISO in Windows Explorer. Can you browse the files? Does the total file size match the expected original? If you see a "Disc Read Error," the conversion failed. Here is where most guides fail