LAS VEGAS HAS BEEN TRYING for years to expand its image and become a family entertainment center. Some skeptics have reacted as if this idea were incongruous, but, hey, even alcoholic, chain-smoking, showgirl-chasing gamblers have families.The idea of a heartwarming, G-rated Vegas started with the 1968 opening of Circus Circus, where trapeze acts are performed over the slot machines. Other hotel-casinos were slow to pick up the cue, but over the last quarter century, the family lure has proven a rousing success: The Las Vegas Convention & Visitors Authority estimates that for the last five years, 6%-7% of Vegas tourists arrivedwith children. All right, so maybe that’s not exactly rousing. In fact, maybe it’s kinda puny. But some Vegans still hope that the family trade will prosper and that, somehow, someday, lovable newcomer Wack E. Wolf will replace Vegas Vic as the city’s symbol. Yes, the taxis still carry ads for the Topless Girls of Glitter Gulch (with the innocent come-on “No cover!”). Yes, guys still stand on Las Vegas Boulevard passing out ads for busty women who offer “hotel room entertainment.” (One man, handing us a flyer, whispered, “Think of this as room service.”) And, yes, the lifeblood of every hotel is its casino. But other states have legalized gambling, so Vegas, having lost its semi-monopoly, needs other tourist lures. Hence the family image. The castle-styled Excalibur offers jousting and Lipizzaner stallions. The Egyptian-themed Luxor has barge rides around the inside perimeter of the hotel. And six times a day, Treasure Island offers a life-size pirate ship sinking a British Man o’ War as actors mime to prerecorded dialogue (“We don’t need them getting wind of our swags!”"You son of a footman’s goat!”). Hundreds of spectators — including at least three or four little nippers — jam the sidewalks for each eight-minute pageant. So, you bet, the city is taking small steps toward becoming a magnet for vacationing households. But one cabbie said: “The problem is, Vegas needs a theme park to lure families. And from what I hear, MGM Grand ain’t it.” Always trust a cabbie. The $ 1 billion MGM Grand Hotel, which opened last December, draws heavily on its movie heritage as a theme (what could be more synonymous with blackjack and craps tables than “The Wizard of Oz”?). The wonderful thing about being at the world’s largest hotel (5,005 rooms and 170,000 square feet of casino space) is that no matter what you’re doing there — calling room service, going to a restaurant, hailing a cab — you know that lots of people are doing it at the same time. Lots and lots and lots of people. So if you need to get away from the long lines and the crowds (and you have $ 25 to spend for adult admission, $ 15 during the winter, even if you’re a hotel guest), you might go to the hotel’s very own, family-oriented amusement park. THE ENTRANCE TO MGM’S GRAND Adventures is a brisk five-minute walk from registration (but allow an extra 20 minutes for getting lost; the elephantine MGM Grand may be the only hotel in history in which employees are placed periodically throughout the property to hand out maps.) MGM Grand Adventures covers 33 acres (compared with 130 for Disneyland or 111 for Magic Mountain), with seven rides and nine eateries, like Kenny Rogers Roasters, featuring “wood fire roasted chicken.” Yes, the park has something for everyone. You exit the Haunted Mine ride, and step right into French Street, which is a few steps from the Salem Waterfront. The paddlewheeler Cotton Blossom sits beside a Dutch windmill, which is right behind the Quick Draw and Shoot ‘Em Up shooting ranges. This is a theme park that doesn’t miss an opportunity: It’s EVERY theme. Since it doesn’t have licensing rights to well-known cartoon personalities, the park has created its own generic cute characters, like King Looey the lion, Dinky Dinosaur and Wack E. Wolf. (However, it does have SOME rights, so the park offers such items as the sure-to-please-the-kiddies “Cat on a Hot Tin Roof” T-shirts.) ONE OF THE MOST POPULAR RIDES is the Backlot River Tour — any similarity to Disneyland’s Jungle Cruise is purely coincidental — in which the boat’s pilot promises “a closeup look at movie special effects.” Visitors sail on a jungle river past pseudo-filming of pseudo-films, like the pop-out-of-the-water “Swamp Creature,” miniature boats for “Ironclad,” and a stone idol for “Temple of Gloom” that puts a curse on the boat and destroys the temple (i.e., a couple of lights flash and two pillars sway). In an apparent nod to its Vegas setting, Grand Adventures offers something no other U.S. amusement parks has: two wedding chapels. Does Wack E. Wolf perform the ceremony? “Oh, no,” said a spokeswoman at the chapel. “It’s all very tasteful here.” The goal is to lure Nebraska families to say, “Pack up the bags, get the kids in the car, we’re heading for the MGM Grand Adventures.” A spokesman for the park said it’s working: Maximum capacity is 15,000, and although on Presidents Day there were only 6,200 due to “crummy weather,” he said everyone expects to be operating at maximum by summer. And maybe they will: This could be Vegas’ very own Disneyland. Or its very own Euro Disney. Recently in a hotel restaurant, one patron was heard to ask the waitress, “The baby put a Keno crayon in my coffee, can I get a fresh cup?” It’s a heartwarming sign that maybe Vegas is becoming a real family town after all.