Is thrr a functionality by which a radwindow can saved as a pdf on a button click event(basically a save as button on the rad window so that users can save the page on their local m/c)???
This isn't offered by Telerik, but what you're after can be easily done using the ABDPDF.NET control from www.websupergoo.com. Their control allows you to create a pdf document by specifying the url of a web page - it takes an image of that page and saves it as a pdf document. There is a free option of that control if you link back to their site, and to purchase it is quite reasonable. All you need to do then is add a button to fire the necessary server-side code to create and save the pdf. Their control also allows the pdf to be written to the response stream.
Let me know if you need further assistance. And I can try to help.