In reply to SuperLee1985:
If you are prepared to drive then The Tyn-y-Coed in Capel Curig is good. In Bethesda itself, tripadvisor.com reviews suggest The Bull is good, but I haven't been there myself. I have been in The Victoria, and would definitely give it a miss.
Couple of my friends ate at the Vaynol last week, and were not impressed.