@Craig_C 

It will not work. In general, you will not be able to reach the LAN side from the WAN side because of NATing. This router is meant to connect a local network to Internet. However you can still use it to route local traffic using VLANs on its LAN side, but that would be a rather strange solution if that's the only purpose of it.

  @Craig_C 

I can only tell you how it could be configured on ER7206 since I do not own ER605. I believe the firmware on both routers is very similar.

You should have ‘vlan1’ already on your router. I think it would be best to leave it alone and create 2 new VLANs. Here’s an example.

First, create 2 new networks.

Name: LAN120

IP Address: 192.168.120.1

Subnet Mask: 255.255.255.0

Vlan: 120

DHCP Server: Enabled

Starting IP Address: 192.168.120.100

Ending IP Address: 192.168.120.199

Name: LAN130

IP Address: 192.168.130.1

Subnet Mask: 255.255.255.0

Vlan: 130

DHCP Server: Enabled

Starting IP Address: 192.168.130.100

Ending IP Address: 192.168.130.199

The above should create automatically 2 new VLANs, ‘vlan120’ and ‘vlan130’. Edit ‘vlan120’ so it includes only Port 2 as UNTAG. Similarly, edit ‘vlan130’ so it includes only Port 3 as UNTAG. You can also remove these 2 ports from ‘vlan1’. Then change PVIDs for these 2 ports to PVID 120 for Port 2 and PVID 130 for Port 3.

That’s all. You can connect end point devices to these 2 ports or unmanaged switches. The router should route traffic between all VLANs without any further changes.

  @Craig_C 

This routing table tells little about your configuration. And, it tells nothing about your VLAN configuration.

"I'm also unsure about the IP addresses for each network as we are using static entries on each side so no DHCP required."

You have 2 subnets, 192.168.1.0/24 and 192.168.120.0/24. You can use any IP address from these subnets except those ending with .0 and .255.

"I have set the ip address of each LAN port on the router to the address of the default gateway for each network, so in my case 192.168.1.1 & 192.168.150.50 should I have done this?"

I don't know what you mean. This is not this kind of router where you can assign an IP address to a LAN port. Did you wanted to say that you set default gateways on your endpoint devices to the router LAN addresses in corresponding subnets? That would be correct. Where does "192.168.150.50" come from?

"As it stands I can ping from a device on each network to the other LAN port on the opposite network but I am unable to ping a pc or anything connected to each network from the other? "

What devices do you try to ping? Are they Windows machines? If yes, have you modified the Windows firewall rules so it allows pings from remote networks? Windows also uses the concept of 'Private' and 'Public' networks.