Having a similar problem here. I purchased two DVDs for my daughter and one won't play. They are from different manufactures. I too am getting a message about libdvdcss but I have libdvdcss3 installed and libdvdcss is not in the repository.
I have tried the DVD that doesn't work on our home player and it runs okay.
If you get too big for your britches, you will be exposed in the end.