I'm trying to use smartripper to rip some of my DVD-R's. I'm trying to create some .mpeg's with these, but smartripper is unlocking most of the files and then giving me a message "some files are locked"

I get this on lots of dvd-r's, about 4 out 5 so far. Any idea why? Is it possible to rip the files with another program like dvd decrypter or not? Can I even do this with a dvd-r I don't know how I created this dvd-r's, it's been a while. Probably with dvd2one or whatever I used before that

thanks