Good topic, LUHE.
The movie 'Alien' was well done. It came out in 1979. It was just a man in a rubber costume but it was really realistic. 'Jaws' was also incredible.
For me, CGI in today's films take away from the realism as opposed to adding to it. Some really bad ones, in my opinion: A Perfect Storm, 2012, the latest King Kong...especially the Godzilla monsters he fought at the end, World War Z. All of the 'Hulks' are so computerish (except for the TV version of Hulk)
Some goods ones, or at least some scenes, have been done really well, though: The plane crash in 'Castaway'; 'Rogue One', 'District 9', and the Lord of the Rings trilogy. The most recent 'Jungle Book' movie was pretty decent.
I was kinda torn about 'Life of Pi'. The tiger sometimes looks real, sometimes fake.
Just some of my opinions.