Don't worry, I went through similar when I was learning.
A) you want untagged, it means any untagged frame that enters the port belongs to the vlan that you have set as untagged on that port. Think of it like this, you want to plug a pc into that port, the pc has no knowledge of what vlan it is going to be on. The frames coming from the pc will not have vlan data. I.e. It will be untagged. You have configured the switch so that untagged frames coming in on that port will belong to the untagged vlan. You can only have one untagged vlan per port.
Setting a tagged vlan on a port is for devices that are able to understand tagging. Things like VoIP phones, access points, nics on virtual hosts where virtual machines need to be on different vlans, and vlan trunks between switches. For example when you first plug in a phone, it might initially connect to the untagged vlan, the dhcp server may be configured to detect the phone and send back details of the vlan it should be on. The phone then connects to the tagged voice vlan. You can have many tagged vlans configured on a port.
B) I don't know that brand of switch, but basic vlan routing should be fine. Turn rip off.
C) I think you want admit all, otherwise untagged frames will be dropped..
D) the ip that you give the vlan on your layer 3 device, Is normally the address that is then used for routing once you have enabled it. The ip is set once per vlan. When you configure your client the default gateway is the address you gave the vlan on your switch. Don't use the Virgin media router address, that would probably work for getting the Internet on your server vlan, but not on the others, and routing between vlans would not work. With the default gateway on your client set to the vlan address on the switch, traffic not destined for the local subnet will be sent to the routing interface for the vlan. If the switch does not have knowledge of a local destination to send the packet, it will use the default route, which I hope you have set on your switch as you Virgin media router. If the switch knows the network, it will send it out of the interface for the appropriate vlan.
I hope someone can explain better that me, I'm a very visual thinker, what is clear in my head is surprisingly hard to put into words.
It's not just vlan theory you need, you need a basic understanding of how routing works too.
Good luck.