I'm going to make a guess that you have a lot of things listed under the "connected devices" page
no the stalk-stalk offering wont be any use as it will be locked to their network settings, your options are get a secondary router that will provide wifi based dhcp service to one group of devices whilst the tg582 will provide dhcp to a smaller wired group on a separate network setting, something like the buffalo airport (sub £20) would work
this would limit the connected devices list to under 10 on the tg582n, and should prevent it from freezing up
your other option is to get a router designed for the number of devices your trying to connect to it, personally I went for option 2 and got a billion 7800dx (but that's a pricier option) which I only need to reboot once a month to stop it doing odd things :)
just because your paranoid doesn't mean they aren't out to get you