MARBLEHEAD-Windows – it’s more than the name of a software operating system.In Marblehead it’s one of the hottest issues facing the Old and Historic District Commission.Selectmen will soon hear an appeal of a commission decision on windows. W. Charles Bridges is appealing the April 7 denial of a Certificate of Appropriateness at 17 Middle St. The request has been referred to the assistant town counsel, who will determine a date for the appeal hearing.Old and Historic District Commission Chairman Pat Patrick appeared before the selectmen Wednesday night to discuss his commission’s approach to double-glazed, vinyl-clad windows, which are energy efficient but not historically authentic.”Our policy is not to allow them,” he said. “These things look like Tinker Toys? If we begin to allow them pretty soon we’ll have Disney World.”He said homeowners had other energy-efficient options, like weather-stripping, and estimated that only 40 percent of the towns with historic districts allowed double-glazed, vinyl-clad windows.Selectman Harry Christensen said some companies are designing the newer windows to look like historic windows.Under questioning from the board, Patrick admitted that the policy is not in writing but appears in the guidelines people receive when they apply for commission approval of a renovation.Selectman James Nye asked Patrick if he meant that every home outside the district looked like Disney World. “That’s not what I said,” Patrick told him.Questioned further, Patrick admitted that the commission took window changes on a case by case basis and had approved the windows in question from time to time.”We do approve these types of windows from time to time,” he said, “on the weather side of a house that faces the harbor, for example.”