It says the installer disc is blank (note there is a difference between disk and disc)? That may mean the optical drive is bad since even if you were putting in a Windows disc or a later version installer it should still read the disc. Does the disc appear in another computer?
What's the difference between a "disc" and a "disk?" - http://support.apple.com/kb/HT2300 - optical cf. magnetic.
The computer is reading it as a CDR. The same iMac will read other installer discs, so for some reason it is just this program. (Digital Performer 5 came with two discs. One with the program on it, and one with "extras" on it. The funny thing is the iMac reads the "extras" cd, but not the program.) The MacBook reads them fine...eventhough I can't actually install them on that computer. I'm wondering if at some point in the past I inserted the disc and pushed a button telling the mac what to do with it? Now it wants to do that every time? That's just a guess...I've never ran into this problem before. Thank you so much any advice you may have!
It could be that particular disc is marginal in that particular computer. Other discs may be just okay in that computer, and that disc may be just okay in other computers. One solution would be to duplicate it and burn it to a new CD. Select a slow burn speed to get a good burn.
Kappy's post: Duplicate a CD or DVD - http://discussions.apple.com/message/8965494
Another solution might be to put the installer files onto a flash drive, or even create a disc image of the disc onto a flash drive and use that mounted image to install on the computer. What is necessary will depend upon the nature and degree of security the installer uses.
If it absolutely insists upon using it from that disc, you could even try putting the new computer into Target disk mode and borrowing its optical drive. There's also drive sharing but I would have to check if that works with Leopard OS.