A router will always provide more protection for your system than not having one. It will make it so the only way a malicious attempt can be made through the ports opened up on the router, those ports must also be forwarded to your computers local IP on the network. Many routers these days have a hardware firewall built in as well to further the protection. The best protection is keeping your anti-virus and anti-malware software up to date. They will catch most anything coming onto your computer. A router will be better suited security for actual attempts to access your system remotely by so called hackers.
Satterly thanks for your message, we had a discussion about routers at our last computer group meeting and I liked the idea of added security..I presently have all the software needed to suit my needs, the physical touch of a router will be added, your description is very clear and to the point.