Bit of an open ended question there jambo222!
There's no shortage of great restaurants/bars in the Old Town, New Town and everyplace else in between. There's so many, it's impossible to single out just a few.
Depends on what you're looking for too:
...food-wise: fish, steak, tapas, burger and chips, vegetarian, etc. and
...drinks-wise: live music, quiet spots to watch the sun go down, pool tables and internet access for the 14-year-old, Irish/British bars, etc.
I sound like a holiday rep here now

, but Puerto del Carmen has all of the above