what spanish should i go for
Well, Spanish is spoken in almost all Latin America, Argentina, Paraguay, Chile, Venezuela, Panama, Cuba, Mexico, etc.
It is not that Spanish from Spain is more spoken than the Spanish from Latin America or the other way round. It has to do with the accent, pronunciation, intonation and some differences in the meaning of certain words.
Spanish is one language, what varies is what i listed above and the region where it is spoken. The same happens with English: New Zealand , American, Australian English, among others.