If you are going to put a cabinet in, I would terminate your cat5e's onto a patch panel, and then patch them into the network switch.
Yes, the network switch is 'fed' with a single network cable from your BT router or 'hub' as they like to call them.
I would prefer to see a branded name for the switch, but thats being picky really.
For smaller home office and small office environments we have used these in the past:
Select the 24 port switch option - Complete with cabinet, patch panel and switch, £118 + vat.
http://www.comms-express.com/products/6u-patching-cabinet-kit/Need some patch leads too, and these days they are dirt cheap - 30p each.
http://www.comms-express.com/products/booted-rj45-patch-leads/Why have they got two LAN ports on the machines?