Best Parsifal on DVD for a newbie to this work?
These two seem the main options 
Yikes. Boring and dusty. At least the MET (more boring, more dusty, but only slightly) has Waltraud Meier and Kurt Moll, but still I will not likely ever watch that Parsifal again.
I am interested in the
Haitink Zurich Parsifal, but haven't seen it. Maybe my colleague has and he can let me know what he thinks of it. Wait... I think my boss saw it, too, but with a different cast that included Jonas Kaufman.
I've heard Ventris in Parsifal in Paris, and he was fine. Michael Volle is a superb Amfortas. (Bernd Weikl, not so much.)
I can whole-heartedly recommend Nagano's Parsifal, though. Best staging--by far--of the four DVDs I've seen (there's an older Domingo one, too).
Ventris again, and W.Meier (yay!). Salminen is a 2nd best choice after Moll for Gurnemanz, I can't stand Hampson in anything, really, but he's not too disturbing here. (And many people seem to like him. I only really like him in Busoni's Faust, but again, that's a personal dislike--like an allergy--more than a qualitative judgement.)
It's also the best filmed Parsifal, not the uninspired "3 cameras in opera house" mix.
Nagano is better on record than live, I find. He ain't no Thielemann... but he can get the orchestra to sound magnificent; he gets through the score without fussing about... there's much to enjoy. In any case preferable to Horst Stein and to my taste, too, to Levine, whose flowery perfume, so liberally applied, gets on my nerves after a while.
