The way I understand it, you're allowed to make one copy of a TV show for your own entertainment. You can of course let family and friends see it (as long as you don't charge them for the privilege). Making extra copies or making money out of selling or showing the shows is illegal. I stand to be corrected but I think that's more or less the situation.
Although technically it is breaking the law, if those people at boot sales selling the latest films on DVD before its out for general release can do it so brazenly without fear of prosecution then I wouldnt worry!