I have a few.
Crash
A Beautiful Mind
Gladiator
Titanic
All won best picture, all are overrated. Others include Star Wars 1, 2 and 3.
I noticed a trend in the last 15 years or so, as long as you can pack as much CGI into a movie and forgo things like a good story, interesting characters and honest to goodness practical special effects people will think it's the best movie ever made. I'd like to go back to when movies were actually good and didn't insult audiences intelligence. Movies like.....The 'Burbs!