Can you play other Blu-ray discs with VLC? If you can, the reason maybe your Blu-ray discs have some problems. If can't, the reason is VLC. As I know, VLC does not support playback of commercial Blu-ray discs with copy protection. Those require decryption keys, which only a commercial player can provide. The reason is that direct playback of commercial Blu-ray discs is restricted and requires decryption keys. Without internet access to a decryption server or a standalone player with the keys built-in, they will not play.
So you need to download a professional blu-ray player, and you don't mention your OS, then I recommend you Macgo, Which has two versions, you can play blu-ray on both Mac OS X and Windows.
You can download here: http://alternativeto.net/software/macgo-blu-ray-player/