You can think that '사람들이' is left out, if this helps. The whole phrase would be '저는 사람들이 xxx이라고 합니다'. 이건 김치라고 합니다. This is called kimchi. / People call it kimchi. / For this, people say kimchi. 저는 xxx라고 합니다. I'm called xxx. / People call me xxx. 하다 has some meanings other than 'to do'; 'to speak', 'to say', 'to call', 'to tell' etc.

Yes, it is but it doesn't sound weird at least to me. I think it's just a matter of a personal preference.^^ However, I'd say "저는 xxx 입니다" when to introduce myself. "- 라고 하다" or "-라고 불리우다" means "to be called" as Joshua mentioned above. For example, 1) A : How do I address you? 제가 (당신을)어떻게 불러야 되나요? B : Please just call me Pascal. 그냥 파스칼이라고 불러주세요.^^ 2) This is called "찜질방" in Korea. 이것은 한국에서는 찜질방이라고 불려진다. = 이것은 한국에서는 찜질방이라고 한다. 3) The waters between Korea and Japan is called "the East Sea". 한국과 일본사이에 있는 바다는 동해라고 불려진다. "-라고" is often found in the reported speech but in here it just indicates "to call A B" and translated as "A 를/을 B 라고 부르다/하다" in Korean. ^______^

It means "I am called...." Such ways of saying one's name are common in other languages, as well. Take Spanish or French, for example. As to the '-라고' ending, '라' is a variant of '-다' (from the typical '-다' style of address: -(ㄴ/는)다 (statement), -(으)라 (command), -자 (let's...), -(느)냐 (question)) when used with the copula verb, 이다. The '-고' ending on that in turn indicates that it is quoted speech. So '...(이)라고' followed by any verb indicating speech or reporting something means "says is..." or "is called...."

you're right! its just another way to say "my name is__" It literally means: "i call myself___" but since it is 저는 and ends in ㅂ니다 , then it is very formal :)

사극 보면 맨날 듣는게 저는 ~라고 하옵니다인데 ㅋ