The problem that you are experiencing is not a Generations problem.
If you were able to open a Generations family file on a CD in the past you were probably using a CD-RW (rewritable)disk.
I suspect that you are now using CD-R disks. It is impossible to open Generations family files directly from a CD-R disk because those disks are read only. You need to copy the family file from the CD to your hard disk, and then open the family file from there.
As you are using old versions of Windows, you will also need to right click on the family file that you have copied from the CD to your hard disk, then click on Properties. In there you need to remove the tick (remove the check mark) from the Read Only attribute, then click OK. People using Windows XP do not need to do that job because XP removes the tick automatically.