Have you checked whether the rest of your hardware is compatible with OVM server? At least the network card/s should be supported. In the end Oracle VM server is placed on top of some kind of OEL 5.x so, you should check that.
If your CD-Rom is not supported, I'd turn either to a HTTP-Install instead of a FTP one (just a personal preference) or you might be lucky with creating a bootablr USB stick from the VM server iso, if your host supports booting of a USB thumb drive.
I did successfully do the install using a USB stick. A bit tricky to do, on my first try I actually did the install ONTO the USB stick, thereby creating some kind of Linux boot stick.
But, once I figured out a few details, the install worked and I now have Oracle VM Server installed.
Here's the sequence:
Created Linux USB boot drive using unetbootin software:
***Here's a tricky part, after I created the USB boot drive, I copied the ISO file (not expanded) to a directory called /ISO on the drive, so at this point, I have the expanded ISO file on the root of the USB drive, and the non-expanded ISO file in a directory on the USB drive called /ISO.
Set the bios to boot off the USB drive.
Boot the server onto the USB drive.
Select Hard drive install and entered /ISO as the path.
***Here's another tricky part, when setting up the which disk should have the master boot partition, I was given a list that had my USB drive as the first option. If you leave the USB drive at the top of the list, you end up with Linux trying to boot off the USB drive. I needed to go into advanced settings and move my USB drive down to the second option to boot from.