The Eurozone has been hampered by one of the major European economies, the UK, not wishing to join. I don’t think the Euro will fail, despite the USs and UKIPs prayers. Of course the different parts of the Eurozone develop at different rates, any part of any country does, ask the people in the North East of England.
If the Euro fails, one of the major losers will be the UK, followed by the other countries whose currencies are set at the wrong rates, and nobody can predict how the world markets will react to the uncertainties caused by a major currency failure.
The US Dollar will benefit in the short term, before the Far East bring it crashing down.
I don’t know about Spain, specifically, it has received an astonishing amount of support from China in recent years, and can devalue with a re-emerging Peseta to bolster its exports. The already healthy tourist trade will increase and the wealthy and welcome foreigners can take up the housing slack.
I have refrained from mentioning that I will be much better off on a personal level, should the one-in-seven-chance scenario come to pass.