I thought I might be able to clarify. It seems "How are you called" would be an invitation to respond with nicknames that your friends gave you, as well as the name your parents gave you. "What is your name" seems to only ask for the name your parents gave you. I'm assuming one is used to be more open to someone, and more informal, while the other is meant to keep a respectful distant between each other, as in a formal situation.
That being said, I don't travel around enough and most of what I get is from books. Am I on the right track?
Зовут is 3rd person plural. Such structure is common for Russian pseudo-passive when an action is performed by unspecified "persons":
- Так не говорят. = People don't speak that way.
- Говорят, что это невозможно. = It is said that this is impossible.
- Здесь строят дом. = A house is being built here.
The pronoun они MUST be omitted for such usage.
Yes, "вас" is the formal/plural form of "you" in the accusative case (corresponds to "вы" in the nominative case). "Тебя" is the informal variant (corresponds to "ты" in the nominative), so you could say "как тебя зовут?" This would be considered rude with an unfamiliar adult, but you might use it with an unfamiliar child, for instance.
The casual singular is ты. The polite and/or plural "you" is вы.
The choice of "you" also affects the agreement, e.g. "Ты смотришь фильм"/"Вы смотрите фильм". In the imperative, -те is added for the plural/polite you (скажи/скажите, извини/извините, здравствуй/здравствуйте)
ты is a singular "you" (Middle English: "thou"), вы is a plural/polite "you". Each has its own forms:
- У тебя есть кошка. Это твоя кошка. Ты молодец.
- У вас есть кошка. Это ваша кошка. Вы молодец (молодцы, if talking to several people).
Politeness shows "respect" as well as some distance, so it is used with strangers and/or people your superior.
- ты is used inside one's family, regardless of age differences between the speaker and the listener
- ты is used towards kids regardless of the speaker
- ты is used by friends
- вы is used by kids towards adults outside their family
- вы is used by adults who don't know each other all too well
- вы is used towards your professor or your boss (unless you are in a tight and friednly company where everyone is on a first name basis and knowns each other)
- вы is what typically gets used by a computer asking a user to do something
- ты might be used by a stranger who is much older than you (like, 60 if you are 35). You are still expected to use вы in this case.