Judging by the daily barrage of gloomy headlines, it’s hard to believe the recession can mean good times. But retail sales tell a different story. What’s flying off store shelves these days? Booze and condoms are among the top sellers. Marketers say their surging popularity is simple to explain: people aren’t going out as much, but that doesn’t mean staying at home has to be boring. Other items that made it onto Nielsen Co.’s list of best-performing retail products include canning and freezing supplies, baking supplies, and fresh foods. Cookies, bottled water, and air fresheners, on the other hand, have seen sharp sales drops.