I'm having a similar problem with VLC 2.0.0 and 2.0.1 on OS X 10.7.3.
Since I was having problems, I uninstalled VLC 2.0.1 and used the script that comes with the app to trash the prefs... after running the script once successfully, I ran it again and got a message saying that it was not able to find any prefs, so it seemed to work. Next, I installed v2.0.0, since I still had the dmg in my Downloads folder and tried using it...
In 2.0.0:
When the source video_ts directory was a home movie DVD on my local drive (that works fine in Apple's DVD Player), VLC crashes.
When the source video_ts directory was a DVD that I ripped (Sneakers), it plays.
When the source video_ts directory was a copy of the same Sneakers DVD files that worked above, but they were mounted via AFP (on my AirPort Extreme), I clicked, "File > Open Disc... > Open VIDEO_TS folder", then I select the Sneakers VIDEO_TS folder, click Open, then the final "Open" button is still grey (so I can't open the files). (The "MRL" text box is empty.)
In 2.0.1:
I am able to open Sneakers on my local disk... when I try to open it up on the AFP mount, it fails to open Sneakers, and decides to open up my MacBook's video camera... great!? (Then I have to Force Quit VLC to get it to close.)
In 1.1.12:
VLC can open all of the above files, on local disk, as well as the AFP mount.
I guess I'm going to revert to 1.1.12 until 2.x is more mature...