Hello,
Why you are going for ITR2 or ITR4? Why not ITR1? First you need to find out which ITR is applicable to you. If you are only an employee and have salary income only and no dividend/interest/agriculture income beyond 5000 per annum, you have to file only ITR1 which is very simple and can be done online. If you are a business man, then ofcourse you have to find other ITR depending upon your status. In such a case, since you are a new person in the matter of online income tax return filing, you should consult some CA for this job. However you may see the link
National Website of Income Tax Department of India and try to understand the online income tax return filing procedure.
Mahavir Mittal