The Ring: Nanako Matsushima (1998) vs. Naomi Watts (2002)
If you weren't already aware, 2002's The Ring was actually a remake of a Japanese horror filmed titled Ringu. In any language, it's a truly terrifying story. Not to mention, each version has a hot-as-hell female lead.
In their respective films, both actresses played the same character, a woman scared senseless after discovering a cursed videotape containing a series of disturbing messages. (See, that's why no one uses VHS anymore.) While Nanako is undeniably cute, in the end, Watts' simple and classic sex appeal wins us over.
Winner: Naomi Watts