Obviously, Leopard is no longer available to download from Apple Store if you do not have a developer account.
Leopard.DMG (InstallESD.DMG) is shared quite commonly on internet. Having Mac OS X Leopard.DMG, it is quite easy to convert Leopard.DMG to Leopard.ISO (available solutions in both Mac OS X and Windows). However, here below are 2 ways to download Mac OS X Leopard DVD Retail 10.5.ISO
Leopard 10.5 DVD Download
The following download links will make it able to download Leopard Installation in both .DMG or .ISO file type.
I, Download Mac OS X 10.5.6 Leopard.DMG
Direct download link from our server
File name: Mac OS X Leopard DVD
File Format: DMG
File size: 6.41 Gb
Mac OS X 10.5.6 Leopard Install DVD.rar (6.41 GB) – Download
How to get Leopard DVD.ISO from Leopard DVD.DMG?
it’s very simple to convert Leopard.DMG (downloaded by the above download link) to Leopard.ISO by using PowerISO in minutes under Windows or Mac OS X.
II, Download Mac OS X 10.5 Leopard.ISO
Mac OS X Leopard DVD 10.5.iso.zip (6.61 GB) – Download
Mac OS X Leopard 10.5.ISO Torrent Download
Due to safety, we do not recommend using Torrent method to download the file.