Our DS6 loves mini-golf, so we play on just about every vacation, no matter where. We played both Fantasia Gardens and Winter/Summerland on our trip in May. Both offer two courses.
Fantasia Gardens has a traditional putt-putt course, themed around the movie Fantasia. Its very nicely done. Some of the holes are kinda hard, but, if you like Fantasia, you'll really enjoy it. The second course at Fantasia Gardens is like a scale model of a regular golf course, with fairways, bunkers, and undulating greens. To be successful, you have to lay up, putt to certain areas, etc. Its like regular golf, with a putter. If you're a golfer, its pretty cool. Otherwise, its hard.
Summer/Winterland is more of a traditional course, where you have to putt over bridges, etc, but all themed to Christmas themes. Christmas lights are strung throughout the course. Its probably more fun for people who just want a relaxing game of mini-golf. Summer/Winterland is next door to Blizzard Beach.
Both courses offer a "second game at half price" deal for the truly obsessed - which, of course, we were.
To puffkin's point about the course being too easy, on several of the holes on both sets of courses, the area immediately surrounding the hole (say, a six inch radius) slopes toward the hole. If your putt gets close to the hole it will often go in. That's probably a real plus for younger kids. My wife jokingly bragged the rest of the day about her expertise.