How to install Leopard in my iMac if it has no DL-DVD player?

Helo\lo, it may read it even if it can't Write DL.

At the Apple Icon at top left>About this Mac, then click on More Info, then click on Hardware>Disk Burning & report what it says, like ...

Interconnect: ATAPI

Burn Support: Yes (Apple Shipped/Supported)

Cache: 2048 KB

Reads DVD: Yes

CD-Write: -R, -RW

DVD-Write: -R, -RW, +R, +RW, +R DL

Burn Underrun Protection CD: Yes

Burn Underrun Protection DVD: Yes

Write Strategies: CD-TAO, CD-SAO, CD-Raw, DVD

Other than that, do you have another Mac around with A DVD player & Firewire?

Do you have another Mac around with A DVD/DL player & Firewire?

My eMac 1.42Ghz reads DVD/RL, it has a Pioneer DVR-127D in it, what is yours?

Most PPC Macs cannot boot OSX from USB, they need Firewire... that being said, out of 13 PPC Macs I had one that booted from USB Drives, including Flash Drives, it was my eMac/1.42GHz as a matter of fact, USB drives would show as a boot choice if I held the Option/alt key at bootup, (nowhere else), but It lost that ability when I reset the NVRAM. 😟

The USB boot workaround that works for some is...

Connect the drive to your machine, and find out which partition the OS X system is installed on. I usually find this by going to Disk Utility and looking at the info for the partition on the USB disk with OS X. That is, disk2s3 is usually for a USB disk with no OS 9 drivers installed that is the second disk disk. disk3s9 might be a USB disk with OS 9 drivers that is considered the third disk. There are other ways of finding this out, but in my case, my disk is disk2s3 (the 3 on the end will come into play soon).

Start up the machine in Open Firmware (this is the fun part). Hold Command-Option-F-F right after the machine is turned on.

Here is the moment of truth. If this step does not work, I have had very limited success getting a machine to boot off USB2. In Open Firmware, type devalias, and you should get a list as output. In this list, look for ud, usually below where you see hd (ud is "USB Disk," I presume). If found, it will usually have beside it /pci@f2000000/usb@1/disk1, or something similar. Again, if you see this, I have not had this fail yet.

Now type printenv boot-device, which will usually get you output of boot-device hd:,\\:tbxi. (See where this is going yet?)

Type setenv boot-device ud:3,\\:tbxi where the number after the colon corresponds to that partition number we found in step two. You should get an ok back.

Type printenv boot-device, and you should see the change displayed already. Something like:

boot-device ud:3,\\:tbxi hd:,\\:tbxi"

http://hints.macworld.com/article.php?story=20060301112336384

You'd need to clone the Install Disc to a Flash Drive, or make a DMG of it then Restore it to the Flash drive.