My favorite is and always will be Buffy, the vampire slayer. She is just so cute and many times she reminds me of myself and I think I would react under similar ways in the situations she is put in. Plus she's a great role model and Sarah Michelle Gellar is my all-time favorite actress.
Willow is not far behing, but in season 5 she went a tad downhill and i can't think why...It's not the lesbian thing, but her relationship with Buffy changed and I miss it...
Then Xander, Anya, Oz, Faith, and Dawn
I also love Giles, although he's far from my favorite!