To make the wireless and 1GB a single LAN (local area network), you would bridge them together. A ‘bridge’ in the term of networking is a device to allow you to connect 2 different type of physical networks – in your case wireless and 1GB wired – as a single logical network.
As for enabling NAT – network address translation – on both WAN and LAN adapters:
You only need to enable NAT on the network connection that is on the Internet – in this case the 10MB adapter. It translates the private IPs of your LAN to requests on the public IP from your ISP (on the 10GB NIC). You wouldn’t want to translate any other connection your network – it wouldn’t go anywhere useful and may cause some loss of connections.
NAT is the software / logic that allows your router to make requests on the Internet for your computers on the LAN. It is used because otherwise your ISP would need to give you an IP address for every computer on your network to access the Internet and all your computers would then be accessible by people on the Internet directly. ISPs charge a lot to give you multiple IP addresses.