I am looking for a server side solution which can capture web content
displayed at that moment on the user browser. The solution GUI will
allows the user to select the area and confirm the screen capture.
Basically the solution will act as a printer driver without the need
to install any software on the client end. I am basically looking for
leads on existing solutions. Thanks

You truly cannot see anything that the user sees on his screen. You
can, of course, attempt to render the content yourself...

Perhaps you might be able to use image maps, but that would mean that
you would have defined anchors (start here, end there)... and if
you're talking about text selection, you probably can forget about it.
Certainly, you can capture the ctrl-c (copy) function, but I'm pretty
certain that you wouldn't be able to know what text was highlighted,
unless you had a hidden form element into which the clipboard contents
were pasted... ooh. Can you say security problem?

You could, I guess, use Java or activeX or something like that. But
that would mean that you'd need the client to trust and accept an
applet from you.

This is a free comment.

Hi docront,

I can make a suggestion, but not sure how well it would work. 

Set up a shared printer on your server. This printer would only print
to file, not to paper. Then have your clients print the web page to
your shared printer. You would then be able to view the printed page.

Regards,
Neutron Coding.

Check this :
http://www.browsershots.org/downloads/
There is (free) software that looks like what you're looking for.