The best way would be to encourage your son to do good. Scolding and shouting at him would not help. I am sure he is not like that always. Whenever he behaves well and listens to you praise him and let him know you appreciate his good behavior. You can also reward him for behaving well. This will motivate him to be good.

Many kids do back talk during the age of 2-4. But its simply a way they want to show that they are grown up and are independent. That does not mean that we as parents will not put a stop to it. But in a way that it does not hurt the child's ego.

animini, for example the situation you described. In such case you can start by asking your kid " Its ok if you do not want to do the job today. But its not the right way to talk to your mom." Take his agreement on it. Then slowly tell him the right way to ask you to do the job. Thats enough for the job for first day.
Next day you can tell him that you are doing all the households and he needs to do his jobs. This all has to be told in a soft and calm way.

Make it sure that you become a good role model for your child. It can be that your child has seen some family member being rude and they are trying to do the same thing. If something like this is happening please let the adults fix their behavior first then correct your child.

I did go through the back talking episode with all the 3 kids at some stage. animini, From my experience what I can say is your son is young now and what he is doing is not at all intentional. Maybe thats a way he want to express himself. You need to sit with him and tell him the right way to communicate.
Let him know that he should respect people and that better way to express feelings are there rather than screaming, shouting and crying.

Only if you have to deal with back talking from older kids you should be firm and let them know that such a behavior is totally unacceptable.

First of all when your child back talks, please be calm and do not respond back to him in a similar manner. You need to set a right example. Talk to him politely and let him know that its not the right way to talk.
What I do is I get down to my daughter and say "You seem to be very angry whats the reason". She may not reply immediately but after a bit of trial she tells me if something was wrong and what she explain. Then I tell her if she does not like what I asked her to do she should tell me. Then I try to explain how she should be going around with things. With these steps I have seen a lot of improvement in my daughter's attitude.

Thanks for all your inputs.
As some of you suggested I am trying to be patient and I have been preventing myself from being rude with him. I have been explaining him also.
Now I am trying some rewards for his good behavior. How long do you think any such technique may take to show some improvements.

My daughter did get into this habit sometime back and she still does it once in a while. I accept once in a while because you cannot make anyone perfect.

What I have been doing is I simply let her know that the way she is talking to me is not right and not acceptable. I tell her that may be she is not in a good mood but she should talk properly. I ask her to calm down and then talk to me. Then I move away from there.

In the beginning she used to get mad when I moved away, and started screaming. Slowly she started understanding. She took are own time cried her heart out and then would calm down and come and talk to me.