Depends on the day of the week, but O'Briens is the best (downtown Temple) by far. OB's is Aggie-owned, has fifty draught beers and probably 200 more bottled beers. Also, you can walk around the corner to the Green Door which is probably the 2nd best in Temple and always has beautiful women if you are looking for scenery.
If you want a unique place with a gorgeous lake view, go out to Belton Lake and sit outside at the Dead Fish Grill.