Someone else had this as well that I replied too.
Have you checked for new firmware for your dvd /cd drive as it might fix something.
Several persons had problems with the actual cd/dvd drive becuase of this.
or use someonelses dvd drive or boot it on their pc to check what might be wrong.
Also could be that it can not fnd the actual chip that controls the ide /ata / hd / dvd drive to motherboard connection and this is blocking it or listing the incorrect drive as the cd /dvd.
Hardware:
Lastly take the hard drive cable if IDE /ata wide cable and plug it into the dvd drive and boot without a hard drive , the current cable might be bad or dying or the hard drive and dvd is on the same cable and some hard drives does not like this at all = slowly killing the hard drive with errors possibly ?
Check the jumpers before and afterwords to make sure they are correct.
Small plastic fuses / jumper at back of hard drive.
Some or all of this happened to me LOL
Will see if I can find that post and list it here .
"lspci" is list pci devices basically and can be done once inside a linux distro as root using the text / terminal screen . No x windows / kde needed for this.
http://en.wikipedia.org/wiki/Lspci
This will show lots of info about the hardware that can aslo block something.
Here is a link about the boot options and or video options that might help.
http://www.sabayonlinux.org/forum/viewtopic.php?t=7496
If all else fails the 3.4 release should be out by 15 june 2007 so might be worth the wait as this fixes plenty bugs like this.
Hopes this helps in the mean time.