Safety is not a big issue on Curacao. The locals are friendly, welcoming, and willing to give assistance. After all, a major part of their island's income comes from tourists. Just take normal precautions for a tropical island and use common sense.
The native language of CuraÃ§ao is Papiamentu, which is a richly unique mixture of Spanish, Portuguese, English, Dutch, African and other languages. Most people from the island speak this language in addition to Dutch, English, and Spanish. Almost everyone speaks English.