Karen
My vote would be Rome or Venice - although never been to Venice & spent Rome in hotel room after eating BAD canteloupe on the plane.
A definite no would be Barcelona. I was so excited to see it after watching the 92 Olympics, but was very disappointed. The Gaudi architecture is amazing, but I thought it all got old after awhile & the Picasso Museum is great, but that was about it for me. But I was there on Nov 1st which is a holiday there, so maybe didn't get a real feel for the city.
Betty