My worst characters would include Monica Hayward from Republic of Doyle. She is the one time the show has ever disappointed me so there is a lot of hate going there, even though she didn't serve much purpose (shady character that flirted with the main character, yada yada yada). Also on my list is Leonard from TBBT. Face it, when you make Howard seem less of a sleazeball you're doing things wrong. I seethe when he comes on my screen.

As for spyware I really like Spybot S&D.