Desperate Housewives everytime. Don't get me started on SATC. Oh go on then since you asked.
SATC started off well but by season four it had become too much about the fashions and not enough about the characters. I hear that even some die hard SATC fans used to watch it just to see what the characters were wearing. There was way too much voice over and the Carrie character dominated the show but I thought she was the least interesting of the four main characters.
DH started brilliantly. That first series had a real macabre feel to it. The other series have been much lighter but it is still very watchable.