For the router you could look into PFSense. I absolutely love it. Use it both professionally (as a firewall/VPN endpoint/access filter/upstream load balancer) and for home setups.

On the NAS side there is FreeNAS, however I don't know the two would interact or if you could directly install both packages into one server (I don't see why not though, even though PFSense probably wouldn't recommend it).