Question : code for an  application which can read a portion of the screen and writes it on another portion of the screen.

can any one give the code for the application which can read a portion of the screen and writes it on another portion of the screen.

here is the two assumptions

1) User navigates to any website and wants to capture the some text written on it and wants to paste it in above the time stamp on the screen. For e.g. User navigates to ABCD web site and wants to capture "Welcome", he will have to specify position of letter 'W' and letter 'e' or mentions that I would like to capture next 7 characters and then the software should copy the whole word 'Welcome'. For pasting purpose user can specify location of 'Start' button on the screen and the copied characters get pasted.

2) User opens a DOS screen and wants to capture the default folder path that is being displayed on the screen. For e.g. Lets say the path being displayed on the screen is C:\folder, then he can specify location of letter 'C' and mentions I need to copy next 12 characters, the application should copy 'C:\folder', similiarly he can specify the location of lower right corner of the screen to paste the values captured.

Answer : code for an  application which can read a portion of the screen and writes it on another portion of the screen.

Here is some code and an article which shows how to build a IE plugin. See if this helps.
http://www.15seconds.com/issue/040331.htm