and dmesg|grep sr is telling you? if i am not far wrong the cd will be found as srX.
and you might have to add the lines in bold to your /etc/lilo.conf:

# LILO configuration file
# Start LILO global section
append = hdc="ide-scsi" hdd="ide-scsi"
boot = /dev/hda
prompt
timeout = 50
then it is time to check where the links /etc/cdrom and /etc/dvd point. they should be pointing to the right device (that you got from dmesg|sr if i am not all wrong).