So if I want to burn data CDs and password-protect (or encrypt) them, what software app's best?

^^^That should’ve said “DVDs” not “CDs”…^^^

I’m just doing PC data backups where I want to have files on my PC copied to a DVD. (Same question as regards external hard drives, by the way.)

I’d like to be able to password-protect or encrypt the thing. But without having to have a special application to open or decrypt it later. (Just the passcode.)

What software do you like for this?

Kinda like Truecrypt for full content encryption would be only useful, any other paswwording is not useful.