Renee Zellweger
Although best known for her roles in hardcore chick flicks and romantic comedies, Renee Zellweger isn't completely unknown to lovers of horror movies. Although her squeeky, oddly child-like voice seemed like it should doom her to nothing but comedic roles and voice-acting, she has the acting chops to be the only really interesting thing in "Texas Chainsaw Massacre: The Next Generation" and bring a unique quality to the role of a doomed prostitute in the under-appreciated thriller "Deceiver".
Unfortunately, early box office numbers indicate that Zellweger's latest horror excusion, "Case 39" is going to be a failure in US theaters, which is likely to curtail her appearances in such genre pictures in the future.
Jodelle Ferland
Although only 15 years old, Jodelle Ferland already has an impressive list of horror films to her credit. Perhaps her generation's greatest "Creepy Girl", she has brought vulnerable spookiness to "Silent Hill", "Seed", "The Messengers", "Twilight: Eclipse", and the just-released "Case 39."
Ferland is still growing and developing as an actress, but she is obviously very talented. If she can navigate the transition from child actress to adult performer successfully--both on a personal and a professional level--I predict great things from her. And as a horror movie fan, I hope those Great Things will come mostly within the confines of the genre, although I think she'll be capable of taking on any role she chooses.