Welcome to the forum! Compared to most fan forums, this is a civilized and intelligent place with a lot of interesting ideas floating around. Jump right in and post, there is no seniority here - new posters get just as much respect as us old crocs.
My favourite characters are Buffy, Willow and Angel. I don't really hate any character with a passion though Spike without a soul is pretty low on my list. I really like the first three seasons best but I can watch just about every one except season six frequently.