Missing movie start

Hi,

after ripping a DVD-to-DVD copy I found out that some seconds at the  
beginning are missing. If I watch the vob files in VLC the movie  
starts with an animation for '20th Century Film' and 'Lucasfilm  
Ltd.'. But in the avi file it directly starts with the real movie. So  
it's not a serious issue but I would like to now a reason for this  
behaviour.

Can it be that the animations are in a hidden track like you can have  
a CD track before the 'first' one that is usually neglected by CD  
players and rip software? Do you have an idea how I can check that  
and if there is possibilty to add some transcode options so that the  
animation is added to the avi too?

Regards

Michael