i want to open on button click. but after radwindow open in outside of that page, means hide aspx page only show the Radwindow content and after clicking on inside radwindow cancel button then hide radwindow and show the that aspx page
I am not quite sure that I understand your scenario, but I think that you want to hide the browser window when a RadWindow is opened. If this is your requirement, it is an impossible scenario because the RadWindow control is based on an IFRAME and it behaves just like an IFRAME - cannot persist outside of the browser window. In your case, however you can make the RadWindow modal and set a not transparent overly. This will hide the parent page's content and you can achieve it by overriding the TelerikModalOverlay CSS class as follows:
I believe that this page will be helpful in order to open the RadWindow. Also, you can close the RadWindow control by using its client-side API described in this help page.
I hope this helps.