Andrew,

It might depend on if the Jetta has ODBII.  If so, you can get a cable
that will give you check engine codes and a lot of other information
(stored or real-time live running).  The check engine codes can be entered
into the program for the DVD for the Bentley and it will give information
and hotlinks on what components might be out of tolerance to generate the
codes and guidance on repair with pictures.  This might be valuable for
you or a mechanic.

Werner

I'm looking to get a Bentley for the Jetta 3 and the parts store has two
options. ... I'm trying to decide which one to go with - print or DVD.
Thanks in advance, Andrew