The first step to creating the perfect hit rom-com is the selection of the leading lady. Remember: she can't be ugly, because women are just as shallow as men and don't want to root for anyone who can't keep up appearances; but she can't be too pretty, either! You don't want the females in the audience to feel inferior.
If she is too pretty, make sure to ugly her down with some glasses or a ponytail, and maybe add in a "quirky" personality for good measure. Of course Jennifer Lopez is a geeky hippie who can't land a man! It's totally believable! It's even better if you can have your girl transform in one of those oh-so-important makeover montages! Doesn't every girl want to see an ugly girl go from nada to Prada?
Select from this list of possible leads: