I don't root against anyone necessarily. I will root for some underdog teams like MTSU, Oklahoma State (not so much an underdog in recent years, but still in a pretty significant shadow of other Big 12 schools) and the Air Force Academy.
But I am often overjoyed when Bama, Florida, Florida State, Vanderbilt, Texas, USCw, any Big 10 team and Ole Miss loses in football.
Women's Basketball: Love watching Baylor and UConn lose.
Men's B-Ball: Kentucky, Kentucky, UK and Kentucky
Pretty much Bama in all sports I love to see fail.