Here's what I wrote to another poster on this subject:
I just played Fantasia and Winter Summerland courses on Sunday. Fantasia Gardens has two courses (The Gardens and The Fairways). The Gardens course is the one you will want to play. The holes are really cool and challenging. The Fairways course is basically a golf course..no fun there. I shot a one under 52 on the Gardens course. Par is 53.
Winter Summerland also has two courses and it seems to be generally less busy than Fantasia. Their two courses (Sand and Snow) are both really fun although I only played the Snow course. Both courses are extremely fun to play with all the characters and such. I shot much better on that course. I had a -21 35 on that course. Par is 56.
These were the only mini-golf courses I've ever played where they give you an actually tee time. The price is only $10/per person but I'm sure it's cheaper for kids. You'll have a blast!