Open a terminal window (that icon in the system tray that looks like a computer screen with a sea shell imposed: just left click once). That gets you into command-line operations.
Now. The command to change directory is cd (see the connection?). So, cd to /dev (the device directory).
Now, type 'ls -l /dev/cdrom' without quotes to show the long listing for /dev/cdrom. It should show you something like '/dev/cdrom -> /dev/sr0', to show you that it's linked to /dev/sr0.
To delete /dev/cdrom, just 'rm /dev/cdrom' without quotes to remove the symlink to /dev/sr0.
To make a new symlink to /dev/hdc, ln -s /dev/hdc /dev/cdrom. The order is important. The device to link comes first (the target), and the new device name comes second (link name).
For more information on the use of the ln command, from the command line, enter the command 'man ln' to see the manual pages for ln.
Then give it a try; see if the cdrom works again. Same as the above for cdburner, dvd, etc.
Note: you may have to edit /etc/fstab to add entries for cdrom, cdburner, dvd, etc, for the system to recognize them as mountable devices. I'll hold your hand this far. Now search the boards for the rest. It's all been discussed many times.