Where to go -- first timer

Have been to Europe 5 times but haven't been to Spain yet. Will have 2-3 weeks. Would like to see Sevilla, the Alhambra, Madrid or Barcelona (don't think there is time for both), and maybe one of the pueblos blancos or the Costa del Sol. Also want to stop in Portugal (Algarve and Lisbon/Sintra).

What route would you suggest for a first timer? Which is better: late June/early July or late August/early September (weddings and school make us in-flexible)? I'm leaning toward August/September, but I have heard July and August are horrible...

i would suggest flying the first time, swimming all that way could be trying for a first time

Monique writes: There's time for whatever you make time for ... define your itinerary, and go from there! Anytime after la Virgen de Carmen (16 Jul) beach resorts will be extremely crowded and pricey. So you might want to lean toward late June. If you're going to Lagos (or Faro), forget about the Costa del Sol.

I've read that the Costa del Sol can stink, but I really want to have some relaxing time on this trip. I suppose going at a slower pace is more relaxing that running around getting to beaches. I guess I really need to make up my mind on Barcelona or Madrid so I can get my plane tickets soon. I'm leaning toward Madrid because I want to see Picasso's 'Guernica' badly, but Barcelona sounds really different from the rest of Spain that I will be seeing. Maybe I can fit in both...