Personally, I would go with option B. Then you can still monitor the activity and the firewalls in your router are still protecting whatever you end up plugging into the switch.

This is a switch. Think of a switch like roads in your town. It gets you around your small area, but will never leave that area. A router is like a highway that takes you to a new area. This will not replace your router. Netgear has some good routers, but just make sure it has router in the description. Another thing to consider is your internet type. Your old.router may have been a modem built in as well. Check that to make sure before buying a new one.