Very often, you have to introduce yourself... The most common sentence to do so is:

• Bonjour, je m'appelle Jean.
  Hello, my name is Jean.

To introduce someone else, your wife for example:

• Je vous présente Fabienne, ma femme.
  Let me introduce you my wife, Fabienne.
• Voici Fabienne, mon épouse.
  My wife, Fabienne.
(épouse = femme, see family)

The verb "to introduce" is "se présenter" (1st group verb). It can be used to introduce yourself or to introduce someone.

• Je me présente: Xavier Renault.
I am Xavier Renault.
• Il présente sa femme à ses amis. He introduces his wife to his friends.
• Il leur présente sa femme. He introduces his wife to them. (leur = ses amis)
• Nous présentons Robert à nos parents. We introduce Robert to our parents.

If you want to talk about your living place:

• J'habite à Marseille I live in Marseilles
  habiter (to live) is a 1st group verb.
• Je vis à Marseille I live in Marseilles
  vivre (to live) is a 3rd group verb.

... or about your age

• J'ai 28 ans. I am 28.

So, a good introduction would probably be:

Bonjour, je m'appelle [your name]. J'ai [your age] ans et j'habite à [your town].