VLAN How To: Segmenting a small LAN

[Digilog]

I have IT background but novice networking knowledge. The question is about my home network setup:

Right now I have a setup 2 Wi-Fi routers/DHCP servers (Home 10.20.30.1 & Guest 10.20.50.1) connected physically to my ISP modem/router (192.168.10.x). The Home router is then physically connected to the L2 switch (HP Procurve 1810G) and the Home LAN (10.20.30.x). The Guest router is only for wifi use. This setup is described on the "How To: One Internet connection - Two Private LANs" article. See below for my setup
View attachment 9472
My question is whether I can physically connect to the switch (a) the ISP modem/router, (b) the Home router/DHCP server, (c) the Home LAN and (d) the Guest router/DHCP server without any hickups and ensuring the isolation between Home and Guest LAN's, as below?
View attachment 9473
My switch supports VLAN's. Is this the way? Reading online I understand that I need to (1) setup 2 VLAN's, one for each Home and Guest LAN's and then (2) assign switch ports of the correspoding devices are connected to, to the proper VLAN. Please confirm.

Can someone shed some light on the Tag/Untag/Exclude All setting, please?

Any guidance is highly appreciated.

Thanks,
Panos._

What I would try is use the ZTE firewall and static assign the guest router wan and assign it as the DMZ address in the ZTE DSL modem and use an IP address for the DMZ outside of the network.

If the other routers have an better DMZ setup that a physical port is assigned I would bridge out the DSL modem and use that router for the network and run the guest wifi router on the isolated DMZ
If your ISP (you will have to try this because most DSL techs will not know either way) can assign two dynamic addresses, then I would bridge out the DSL modem and set the routers' WAN to DHCP. Otherwise, the ISP is set up with a client with one dynamic only and have to lease a static public ip for the second network.