Most movie DVDs has copy protection, if you want to copy it to your hard disc, you must decrypt the copyright protected dvd first. Otherwise, Although you copy the *.vob files to the hard disc, but most media players cann't it. My friends recommend me to use "E.M. Easy DVD Copy" to copy DVD moives. The video quality that be copied is excellent. If your dvd moive size larger than 4.7G, you can compress DVD to suitable size.
in addtion to, new version add some funtions like convert DVD to other popular formats, such as h264, Xvid, MOV, VOB, Mpeg, Mpeg4, Mpeg TS, AVI, WMV. so you can watch dvd movies on portable player conveniently.
if you want to try it , you can google it:
http://www.google.com/search?hl=en&q=%22e.m.+easy+dvd+copy%22.