With the GameCube qoob Pro mod you can ripp games to iso files. Beside the mod itself you need also an installed Nintendo GameCube Broadband Adapter.
First your network has to prepared. I have reactivated an old router from me for this case.
If needed it is recommended to set the router base ip address to 192.168.1.1
The default qoob Pro ip address is 192.168.1.32 The ip of the used computer should have 192.168.1.100 (as described here).
If your setup is done insert the game. Power on the GameCube and hold the B button to open the qoob menu.
Open a browser on your computer and open the URL: http://192.168.1.32/DVD
The browser starts to download a file named ‚DVD‚ of the current inserted game. A rip/download takes approximately 40 minutes. If the download is finished rename ‚DVD‚ to a appropriate name of the game.