Car/moped hire in Spain

[itcaptainslow]

I'm off to Spain for a week with a few mates, they're planning to bugger off to a theme park one of the days which isn't really my bag. Therefore, I was thinking of hiring a car/moped and exploring the local countryside.

Any particular companies that come recommended (so I don't end up in a Golf R32 *cough* situation), any tips and anything to watch out for?