We did the open top bus tour, totally worth it. we also went to the guiness storehouse defo worth a visit and also Kilmainham Jail.
I must admit, I first went there about 10 years ago and went back last year and was disappointed, felt it had lost some of its craic. Too many stage and hen parties, if I was you I would avoid the Temple bar
Would recommend Gallachers boxty house to eat though and Thunder Road Cafe (BIt like Hard Rock Cafe).
First Time we went we stayed in Clifton court hotel on Eden Quay, it was really nice and friendly, this time stayed in Central Hotel wouldn't recommend it, staff unfriendly and unhelpful and they seem to rent rooms by the half night, need I say anymore!!!!