HELP! Please send travel advice re: Madrid, Crete, Santorini

Greetings, raptrons. In a week Johnny Quest and I will be taking off for two weeks in Spain and Greece. We'll spend three days in Madrid and then meet her folks in Athens and go galavanting around Greece. Now, her dad's from Greece (came over here when he was eight...very cool story, actually), so he speaks fluent Greek and knows his way around, but he's never been to Crete or Santorini, and we'll be spending lots of time there. Of course we're reading up on our destinations, but if anyone has any advice about these places--Madrid, Crete, Santorini--I'd be obliged if you'd pass it along.

P.s. Please note new e-mail address, in case you want to send info in that way:

philosoraptor{at}gmail{dot}com

p.p.s. As a card-carrying member of the ACL-you-know-what, I'm a little worried about privacy issues associated with gmail. Anybody have any thoughts on that?