In reply to Emma84:
This sort of question gets asked regularly on these forums and is generally not answered well. The reason, I believe, is because the question in itself is based on a misconception. For example: "What is the best rock climb in Britain?" Of course one could give an answer, but how much would it be worth, considering the variables involved (length, setting, rock type, difficulty, history, etc.), and then one has to ask, how many people could possibly be qualified to answer?
What I mean is that talking about the whole of the Dolomites in a sweep is meaningless. If I asked my local Dolomite mates, who have been rock climbing since they could walk and work as mountain guides, they would just look glazed at even trying to make such a list. There are huge areas where they have never climbed, areas they have never even seen. The Dolomites is a massive geographical area with very marked local differences, and more or less infinite climbable rock.
So my advice is to rephrase your question with a geographical limit (like "around Cortina", or ""in the Pale"), a grade bracket, and an inclination either towards sporty or mountaineering. That way you might find somebody who actually knows what they are talking about and get a useful response. (I have been living here for over 10 years and I would only feel qualified to answer for the Sarca Valley, and up to what today are considered "medium grades".)
This is perhaps not what you wanted to hear, but I hope it is useful ...