well I only can tell you that you can't complete all of them, the ques to find zandalor in the inn, when you get there , there is a mark one telling you that he is in the castle.
don't know how many are they.
none of the quest are hard(with the proper equipment), but some took a lot of traveling, like the summoning, the wine, penumbra and the long run to the forest
the funniest quest to me was the brothel, jajajaja, that was fun yeah!!!!
none of the quest are a waste of time, al of them give you the great oportunity of enjoing the graphics and sound of this powerfull game, it doesn't matter if the story of the quest is a little lame, jejejeje
hope that helps <img src="/ubbthreads/images/graemlins/alien.gif" alt="" />