Mine have changed over the years. The Usual Suspects was my favorite for a long time. It was the first movie to completely fool me. As my interests changed I turned to Gladiator in 2000. It was my favorite until Inception was released in 2010. 10 1/2 years strong and it's still my #1.
Last film I watched was Tenet. But my favorite is Who am. Actually it's a perfect film and it's really the best choice to watch something to relax.
I like all kinds of movies from comedy to horror but my favorite of all time would have to be Tombstone. If you have not seen it I highly suggest you do it is a classic.
my fav is Inception! I rly like the whole concept and an open ending. Also the visual part is amazing. One of the best Nolan`s work!