I am converting a .vob file and it only lets me convert a few seconds then stops.

this may be due to the copyright protection on the source disc.

In the United States there are three organizations concerned with copyright licensing - ASCAP, BMI, and SESAC. There is some information on the University of Oregon website (http://darkwing.uoregon.edu/~copyrght/Docs_Html/XII_XIII.htm) that discuss copyright issues. Please read it to gain an understanding of the issue, and some leads to where you should be able to obtain more precise, definitive information.