VLAN help

I am trying to add a vlan network onto my existing network where no traffic is on a vlan. I need to isolate the VLAN traffic on the same network as existing traffic and only allow it to access the DHCP server and gateway of the hotspot firewall not firewall 1. I try setting the port 2 on the bridge of switch 1 to VLAN 250 but it doesn't isolate it and gets served dhcp addresses from firewall #1 instead of the hotspot firewall. I'd like a easy way of doing this as not to impact the existing network and traffic. Any help would be appreciated.


Switch 1

port 1 - regular traffic
port 2 - VLAN 250 hotspot
port 5 - Uplink to Switch 2.


Switch 2

Port 1 - Input from Switch 1
Ports 2 - 10 - Various other traffic
Port 16 - Uplink to Firewall 1


Firewall/DHCP Server #1

Port 1 - Traffic from Switch 2
Port 2 - Connect to Hotspot Firewall VLAN 250


Hotspot Firewall/DHCP

Port 1 - Only VLAN 250 traffic from Switch 1 port 2

Diagram please.
http://forum.mikrotik.com/t/using-routeros-to-vlan-your-network/126489/1