To me, two weeks is a great length of time for a first exploration of Spain. I would suggest Madrid for four days (including day trips to Segovia and Toledo), a day in Cordoba, 2-3 days in Sevilla, 2 days in Granada (to visit the Alhambra, the most popular tourist site in Spain), then up to Barcelona for a couple of days. From Barcelona, you can fly cheaply to Venice on MyAir, vueling, or Clickair, or maybe go to Rome or Florence for a day or two before training to Venice (vueling and clickair go to Rome, Meridiana to Florence). If you like the idea, book your flights first so you know you've got cheap flights in and out....then worry about the rest. Book Alhambra tickets on line ASAP, get Rick's Spain book, and look for lodgings in "hostals," a class of hotel like a pensione....clean, comfortable but cheap. Another option are Ibis and Etap hotels, part of the Accor chain, which are modern and comfortable, if basic. PM me if you need further input.