how to get input from user

Hi all,
I am very new to java scripting. My problem is

"I have a table to display and whenever user double clicks particular row, I have to prompt any editable tab so that i get the values for that particular from the user like rulename, sourceaddress, destinationaddress.etc... and I have to change that particular row values to the user specified one after he clicks save button in editable prompt".

Can anybody please tell me how to do this , wheather its better to use javascript or some other way please guys show me some way how to do this.

Thaks in Advance,
jack

Basic idea:

Add an onclick handler to the row.
Pass the row object to your function
Use getElementsByTagName to get the row's cells.
Read the innerHTML of the cells/

Eric

Thank you very much Eric for quick reply,

1. What Iam not getting is how to display editable tab on double click on the main page.
-->Is it any popup window, as I read many browsers disable popup windows if so what is an alternative, can u please guide me to some example code or any material related to this.

Thank U very much again,
jack