It depends upon the situation, your audience and the topic of your speech. A simple "Good morning (afternoon, whatever), I'm (state your name) and I'd like to talk about (give the general topic of your speech)" is probably find for a five minute speech. If someone introduces you, and therefore has already announced your name, change the sentence to "Good morning, as (moderator) mentioned, my name is __________ and I'd like to talk to you about....."
Is this speech an assignment for a class? Or are you giving an actual presentation to some group? If the audience has assembled specifically to hear your speech, you should also thank them for coming in your introduction.
Student or Learner