Thanks for that advice. It's just that when upgrading to a new Mac, there's all kinds of money having to be spent including new software that one must buy again (such as DiskWarrior) so if the primary software that made the original Disc Images still works, one tends to want to stick with it. I went into Roxio's documentation and they claim that 7.1.3 is considered as a universal application for Mac X although it is no longer supported.
As it is, it seems like a big job to get everything migrated over to the new iMac so the less new software having to be involved, the better. At some point, I would like to buy Toast 10 but if 7.1.3 will work, it's worth waiting for.