Studio HD15, Windows XP Sp3:

I recorded some DVDs of dance from TV in Germany. A DVD of (say) 4 dance tracks (each one between 15 and 60+ min long) has 4 sets of 3 files on it ( a .vob .bup and .ifo for each track, in others words, for each program that I recorded). I simply wish to import selected tracks and convert them to AVI files for my granddaughter's little video/MP3 player [which can apparently handle AVI, WMV, RMVB and FLV formats].

When I try to Import these into Studio HD15, using Import / DVD or Blu-Ray, I only get the first fragment (typically 30-40 seconds) of each dance importing - video and audio intact. The rest appears to be lost/ignored. Sometimes the 40 seconds is broken up into a number of small files.

How can I get the whole dance (ideally in one file but that is not imperative)? Or am I asking this program to do something it was not designed to do?