The look of ankle boots and a skirt seem very okay. I'm assuming that the skirt has to be between mid-thigh and knee-length. It would have to depend on what kind of skirt and boot combination we're talking about. Are we talking about a pleated mini skirt with chic booties? Are we talking about a frilly, girly skirt paired with tough ankle boots (a la Hannah Montana)? Oh yeah... this look also includes the much-beloved open-toe boots I've been opposed to. I'm reminded of an ad I saw in a local newspaper where one femme was wearing this black dress or skirt, some violet tights, and these black open-toe booties with a zipper down the center.
Making this look work really depends on a certain kind of skirt, a certain kind of booties, and (optional) any number of accessories (like leggings or tights). I have no problem with skirt + ankle boots.