BufferZone 

BufferZone is a program to protect your computer from external threats. It achieves this by creating a "virtual environment" in which it runs your web browser, instant messenger, file sharing program and executable file attachments. This way, every action performed by any of these applications won´t affect your system, since they run in an isolated environment. You will be able to know what applications are running in the BufferZone environment by right clicking on the icon in the system tray.

Once you install the program, it will ask you if you want to hide some special folders, or sites. Then, you can specify them. Even the downloading of files will be supervised by the program. This will be indicated with a red border around the downloading window. If you trust a file, and want to open it later, you can right click on it an use the "Open Outside BufferZone" option. This program doesn´t work under Windows 7. It doesn´t require signature updates. Still, it will protect your PC against spyware, adware, and viruses, known or unknown.