So far its the only site I used to choose what to watch next in the evening to spend my free time... Has multiple trackers though and may be unsafe for children - this parameter greatly depends on the movie you choose.
I very much like imdb.com and rely on it for detailed info on movies, TV-series and actors/actresses (also use Google search features but I like IMDb better for details). Ads are standard and non-intrusive. Child safety is dependant on the content you search and choose to look at.
An excellent resource for film enthusiasts, though there is a growing consensus that the film-ratings should be taken with a large pinch of salt as they are subject to manipulation by film makers or immature viewers/browsers. (If you rate a film, please provide a review giving your reasons.)
Members at the IMDb forums can be extremely helpful in identifying forgotten films or scenes and actors. Your intelligent participation can help improve this site.
No experience of malware or popups here. I use an ad blocker. Safe for kids, but they possibly wouldn't find it interesting.