To enable the sidebar functionality in Windows Vista, Click on the Start button, and select All Programs. Click on the Accessories option, and select Windows Sidebar.
The Windows sidebar is a bar on the side of your screen that consists of programs called gadgets. Each gadget offers a different tool, such as a weather gadget, slide show gadget or news headline gadget.
To prevent any open windows from concealing the sidebar, click on the Start button to open the Windows Sidebar properties. Click on the Control Panel link, select Appearance and Personalization, and then click on the Windows Sidebar Properties. Select the check box labeled "Sidebar is always on top of other windows," and click OK.
To download additional gadgets into the sidebar, click on the "+" sign located on the top of the sidebar. Browse through the gadgets, and select a gadget of your choice by double-clicking on it. The gadget should appear on the Windows sidebar.
To download gadgets online, navigate to the Microsoft Vista Gallery, and click on the download button located below each listed gadget. The download should start automatically. After the gadget is downloaded, run the file, and proceed to install the gadget on your PC by following the provided installation instructions. The gadget should automatically appear on the Windows sidebar after installation.