I burned some DVDs on OS X. I can mount and play commercial DVDs on FreeBSD, but not the burned DVDs. No problems on OS X.
Given that the DVDs work on OS X, this indicates to me that nothing is wrong with the DVD. Given that I can not even mount the DVDs on FreeBSD, this indicates to me that the problem is at a lower level than the playback software.
Is FreeBSD simply unable to mount some burned DVDs? (Nevermind the specific filesystem the disk uses for now.)
EDIT: I may have meant UDF instead of UFS, but at this point I'm not confident I know what the problem is.