I think if you keep them in a safe, then you've covered the physical access problem.
With tools such as ISOBUSTER, http://www.lostpassword.com and http://www.knoppix-std.org/tools.html (more tools), unless you solve the physical access issue, then any good forensic analyst will read your CD.
Win XP Pro,Creative CD-RW.
I have transferred some files to cd and for security have protected the files individually.
For extra security, is there any way I can protect the CD itself. i.e. stop unauthorized people from reading the CD.
Thanks in advance for any help.