How to choose the close case layout for the mass close button in a list view?

Hi Ravi,

You can edit / create new case buttons from Setup -> Customize -> Cases -> Buttons and Links.

If its an s-control you can just edit the existing Close button and set it to use your s-control. If you've got a visualforce page you will need to create a new custom button. You can then use the settings:

Display Type: List Button
Content Source: Visualforce Page

Thanks