Xen 5

Xen is an open source virtual hypervisor used in Linux and BSD systems. If you set your security to not allow any services and run a BSd on top of Fedora or Suse- NetBSD is compatible with Xen- you will have multiple layers of security. One being that the second machine has it's own rules and two that the inteface is virtuaal, so you won't lose your machine if some did infect you. You could also try to use firefox and set the downloads to prompt.