That redirects all traffic to tcp/80 (HTTP) to the proxy. To only apply that to 192.168.0.180 - 192.168.0.199, first make another address list, then add a qualifier to the proxy redirects that only fires for traffic sourced from that list:
parent-proxy (Ip4 | ip6; Default: 0.0.0.0) IP address and port of another HTTP proxy to redirect all requests to. If set to 0.0.0.0 parent proxy is not used.
src-address (Ip4 | Ip6; Default: 0.0.0.0) Proxy will use specified address when connecting to parent proxy or web site. If set to 0.0.0.0 then appropriate IP address will be taken from routing table.
You don’t have a parent proxy, so leave that at 0.0.0.0 to disable the feature. If you want traffic to be sourced from a particular IP address on your router (so you can easily recognize it further upstream, for example) you set it here, if you don’t care or don’t need the feature you leave it at 0.0.0.0.
That’s the wrong syntax for defining an address list
You’re mixing address lists and ranges which is a bit funky.
Do you really want this on the input chain? Unless the router itself is hosting the wbepage (or maybe acting as a proxy?) you probably want it on the forwarding chain.
Try something more like:
/ip firewall address-list
add address=192.168.0.161-192.168.0.180 list=NoEntertainmentWebpage \
comment="Note that there are no spaces in the list name, these are users who are denied certain web pages."
/ip firewall filter
add chain=forward action=drop protocol=tcp dst-port=8080 src-address-list=NoEntertainmentWebpage in-interface=ether4-Office-LAN \
comment="Again no spaces in the names for the address list or the port. Port names can use '-' but address list names don't seem to allow it."
Once you’ve added that firewall rule you will also need to move it to the correct place in the chain.