Wireless can be disabled on the TG585v7 as follows:
Browse to the router web interface (192.168.1.254)
Login to the router using the Administrator account
Click Home Network
Click Interfaces
Click WLAN in the body of the page
Click Configure at top right
Untick the Interface Enabled check box
Click the Apply button at the bottom of the page
For safety you should leave the wireless set to WPA-PSK even if the wireless is disabled. One less thing to have to bother about if wireless is later enabled again.
