Sandbox

Hello, I have heard alot about running browsers in  a "sandbox" to avoid driveby downloads.  I have some questions about this "sandbox"

 

1) How does it work and is it effective?

2) Does it work with opening attachments and downloading files?  If it does allow downloads, once a file is downloaded where does it go?  Can it be removed from the sandbox and placed in a normal folder? 

3) Does it conflict with any other systems on a computer?

4) Does it conflict with security software like NIS?

5) How do I get it?  Are there any recommendations on where to get it and is it safe to download?

 

Thanks