If this is a home burned DVD on cheap discs then those are very prone to presenting issues. Handbrake 10.10 Mac OS X Leopard Handbrake 10.10 Software Is 0 Handbrake 10.10 Download Url HandBrake Choose the chapters, basic support for subtitles and some styles make Handbrake to be essential if you want to convert DVD into MPG.
If you still have problems copying the files then it is possible your drive is having problems or the DVD itself is damaged. I'd go with copying to computer first, then converting, otherwise you'll put some heavy use on your DVD drive. You can then use a multitude of applications to convert the file to a more computer ready format. If it isn't copy protected then all you need to do is copy the DVD files to your computer. If it is copy protected and you have right of use of a section then you should contact the producers of the DVD so you can get a copy of that section in regular format. If the DVD is copy protected then it is likely copyright and just the act of ripping a copy protected DVD is illegal in the US and many other places, probably even if you are on it (if somebody has a book of yours in their house you do not have the right to break down their door to get it).
