S&M, but then again I like Don't Stop the Music, but it seems just as tad bit overrated. As a fan it's hard to choose because I love all her music but if I had to choose it'd be between S&M, DSTM, and SUAD? Just because they're the songs with the least meaning but are amongst her biggest hits.
Disturbia is one of Rihanna's best videos and one of the best videos in my recent memory. There's nothing boring about it. I don't see how it's generic when I personally feel like it fits her voice which gives it a type of haunting effect.