Read Win98 media to WinXP

I have some media from my old Win98 that has been backed up onto CD-R’s.

Now my old Win98 machine’s HD is toast.

All i have is 2 other PC’s
Both running XP 1 NTSF and 1 Fat.
When i put the backed up CD-R’s into either of my drives from both machines they come up as if there’s nothing on the discs.
It’s like they are blank and it doesn’t make sense.

Please help!