I need to buy a router so have been reading posts about this topic. I have found several posts/pages that talk about using a router as a firewall...also use it as part of the total antivirus protection for the home/system. Some people have mentioned using an older pc to function as a router or to function with a router to work as a firewall, antivirus, etc. Can someone give me the big picture here of what people are talking about? All I can find on the web are the trees, not the forest