Every time you see a person or want to ask for direction, just begin with Ola! and that's their 'hello' and we realized that as soon as we stepped into Madrid.
Our travel plan consisted of 3 days Madrid and 3 days Barcelona and I think one needs 4 to 5 days atleast to enjoy Barcelona.
Travelling between Madrid and Barcelona is super easy. Just take the Renfe - http://www.renfe.com/EN/viajeros/index.html - Luxury seats!
Will update more in the coming posts - For now this is the where the bull fight was, in Madrid and I still get goosebumps from the experience...