Since my (now) wife moved in with me I've tended to re-watch the cult classics (Re-Animator, Evil Dead, Dawn of the Dead etc.). For a long time we never really got into the obscure movie because I never thought she would like them. Thankfully I was wrong and movies like Sleepaway Camp and Pieces are some of her favorites from my collection.
Now I'm back into watching that pile of movies in my collection that I have never seen with a small number of repeats in between. But there are definitely movies that are required yearly viewing for me such as Back to the Future and NOTLD.