Answer: It depends.
One of the common admonitions on this site is that when you're translating to or from Spanish, you should always translate for meaning, not translate words. Like many other words, "want" has several meanings in English, so you need to pick an appropriate translation if you wish to convey your ideas in Spanish.
All that said, the most common Spanish verb meaning "to want" is querer, which can be used in a wide variety of situations. Even though it can be used in a variety of mundane situations, the verb also can mean "to love" (te quiero is a common way of saying "I love you").
Usually synonymous with querer is desear, which isn't nearly as common as querer. It is frequently taught to beginning Spanish students, however, because it is a regular verb while querer is not. Like querer, desear can have romantic or sexual overtones in some contexts (it comes from the same origin as the English verb "desire"), so you should exercise caution when using it to refer to people.
- Examples: Quisiera dos gaseosas, por favor. I would like two carbonated drinks, please. Quiero una casa grande. I want a large house. ¿Deseas ayudar? Do you want to help?
Where "to want" means "to ask" or "to request," the verb pedir is frequently used.
- Example: ¿Cuánto pide ella por su coche? How much does she want for her car?
- Example: Te buscan en la oficina. You're wanted at the office. (Literally, they're looking for you at the office.)
- Examples: ¿Necesitas dinero? Are you wanting for money? El Señor es mi pastor, nada me faltará. The Lord is my shepherd, I shall not want.

