There are lots of things to do at this park, or you can just sit and relax, or take a leisure walk along the lake. If you have kids, park at the parking lot next to the play ground since it's close to many attractions. From the playground, you can walk down to the river to rent a canoe or kayak, or go to the train station to board the miniature train. Another nice place to visit in the park is the Nature Center, which has a Dino-Pit that the kids can dig up dinosaur fossils.
Try to go on a week day, when the park is not crowded and the parking is free.