The Royal Oak http://hotel-snowdonia.co.uk/ is great for food and rooms, and is slap bang in the middle of Betws so plenty of other stuff around. The stables bar is ALWAYS full of totty too.
There's the Tyn y Maes Lodge in Bethesda http://www.snowdoniamountainlodge.com/ - only drawback is it's about 1/2 hour to the pubs in Bethesda. They have rooms that take 2/3 people.
Let us know when you are over - I'm top of Bethesda so be glad to show you the local roads (and a few sheep or so ....)