I'm not tech savy so bare with me when I ask what

I'm not tech savy so bare with me when I ask what is the best bitrate to view the videos? So far its been fluxuating each time I Iog on the site anywhere from 13-16 bitrates usually sets at before viewing Ultraflix. I'm wondering if the bitrate is the reason I get a lot of delay skips with the circle rotating throughout the movie.