children and friends came to visit their grandmother and are trying to renovate a house in the forest and there are ghosts there
the ghost club
Apologies in advance, since neither of the movies I am about to suggest are a perfect match. But if you saw the film many years ago as a child, perhaps you could be fuzzy about some of the details. Both of the movies are Disney supernatural thrillers that have some similarity to your description. They were made for a young audience. Both were based on well-regarded young adult novels that I read when I was young.
My first suggestion is The Watcher in the Woods, a theatrical film from 1980. A family buys a large house in an English forest. The previous owner, played by Bette Davis, continues to live on the property in a guest cottage. Bette isnât a grandmother, but she is certainly old enough to be one. The older daughter of the new owners begins to have strange, supernatural visions. These visions seem to be connected to the disappearance of Bette Davisâs daughter many years ago. Disney was unhappy with the directorâs original cut of the film, and they made major changes to the film, adding a radically different ending.
My second suggestion is a 1978 Wonderful World of Disney TV movie, A Child of Glass. A family purchases a run-down antebellum Louisiana plantation house and work to restore it to its former glory. The young son of the new owners discovers the ghost of a young girl who died a century before, her body cast into a well in the barn. He teams up with a neighbor girl and her grandmother to solve the mystery of her murder to free her spirit.
Neither of these are close matches to your description, but they do have enough similarity that it might be worth ruling them out.