"Mujeres" will almost always mean "women", but I guess it could be used to mean "females" as well. "Niña", "muchacha", and "chica" all mean "girl", but "niño", "muchacho", and "chico" mean "boy".
I always thought of English as a slimy and pasty language, with its ugly vowels and weak r's and l's. The thing I would find most annoying about Spanish, if I were a native English speaker, would be grammatical genders and verb conjugations.