Very puzzling. It clearly has found the CD drive sucessfully.

mounting /dev/fd0 on /tmp/floppy as type ext2
* mount failed: Invalid argument

These line suggest that what is actually happening is that it is failing to mount the file system on the floppy for some reason.

The way these Linux install boot floppies work is that they boot a Linux kernel from the boot blocks on the floppy, probe for all the hardware they need and then mount a file system from the floppy with the data that they need.

It looks like this mount of the file system from the floppy is failing (unless the log output is misleading and it is a mount that it hasn't mentioned that is failing).

Does the Mandrake install offer any other debug output on the other virtual consoles ? (you can switch virtual consoles by pressing Alt and one of the function keys, with a different virtual console on each function key).

I guess if the floppy mount really is failing you could have one of:
- dodgy floppy disk
- dodgy floppy disk drive
- a combination of floppy disk drives (I have a couple of drives that can't read disks written by each other)
- something else entirely