Lindsay Lohan
3
I'll give her the benefit of a doubt and give her a 3, only because she's young and there's still time for her to develop more as an actress, or simply leave it for a singing career instead.
Right now though, she's everywhere and she's far too over-hyped. She's had some good movies and she's had some good songs, but that in no way makes her some legend of Hollywood. Once she's gotten out of her teens/early 20's phase, she'll be getting roles that let her audience know if she can actually hack it as an career actress.