You'll never guess who seems to be #1. No, actually, you will.
"Who is the worst wife in all of television?" (seen on Reddit AskMen, can't link to it per this sub's rules)
I feel like Walt and Skyler were a triumph of the writer's room. We rooted for Walt, long past the point where he was obviously a really bad guy, and we blamed Skyler for things that were reasonable, occasionally standing in his way, and far smaller lapses of morality.