If you want to experience an extraordinary view while eating quality food, I would recommend you visit Parlament which is located right next to Bratislava castle. In the evening it is more charming as the castle is lit up with tower lights and you also get to see the Bratislava Ufo and Apollo bridges at night from the other side.
I had a Xmas dinner at Parlament and the food was just amazing. We had a selection of Slovak traditional starters (cabbage soup), main dishes (fried fish with a Xmas potato salad) and desserts (wide range). Parlament is a restaurant serving a lunch menu during the week in the afternoon and an a la carte menu in the evenings. The a la carte menu covers European dishes such as grilled salmon, pasta, steaks or salads.
My experience at a Xmas dinner was absolutely great thank to the ambiance and the mostly excellent food combined with a beautiful view of our Castle and bridges.