HIMANSHU BHARTI said:
But I already have a disk
Usually, all the files that you need to install Win7 are on the Win7 disk. So we have no idea what your problem is.
Can you describe the problem you are having? How far do you get in the installation process? What message do you see when the process stops or fails? Can you boot from the DVD at all?
If you are not comfortable in English, I suggest that you write a detailed reply in your best language and run it through Google Translate.