It's an old kids fantasy movie. It has a nice leprechaun,a boy and a girl. They go to stay at a familys members house out in the country where the end up on a small river boat with the lepr. And go to a magical place where people jump into this "hole" and come out these beautiful "animals".(dressed up of course,not literally an animal).

Sounds like The Great Land of Small (1987)

Omg! IVE BEEN LOOKING FOR THIS MOVIE FOR 10 YEARS!! Sorry about caps I am just so excited! I can not believe someone else actually remembers it. My family thought I was delusional. I am so glad I went through twenty pages of questions just to find this one!