Now, needless to say, I was hardly the "target demographic" for this movie, so the fact that I didn't particularly enjoy it isn't too surprising. Not that it was especially bad or anything (to its credit, it hardly dragged at all), it was just one of those things that I would have just as well have skipped. The Wife, though, did point out that she found the movie a bit off as well, and for some similar issues that I was having about it.
First of all, the movie is set in the current time, but the lead character seems to exist in a 1960's time-warp, not only in how she dresses and acts, but her car (how old is Nancy Drew supposed to be?) is a 1960 Nash Metropolitan convertible. The "mystery" that the movie revolves around is focused on an actress who first disappeared and then died, supposedly in the 1980's, but all the pictures of her seem to be out of Hollywood's "golden age" many decades before that. None of these time-line questions are resolved (or even addressed), giving a surreal tinge to the whole experience.
I usually expect to be able to find fairly complete info on a film over at IMDB.com, but there were a lot of odd gaps in the info for Nancy Drew, ranging from "big stars" not being in the credits (SNL's Chris Kattan as a burglar in the opening scene, and Bruce Willis playing himself on a movie set) to very noticeable music (well to me, at least) standing out yet not mentioned (a strange female-voiced cover of New Order's Blue Monday). Makes me wonder what the deal was on those.
It also felt like they had edited out several sub-plots that were sort of left hanging as "connect the dots" relations between various side characters ... in another movie, I'd say this was setting up a sequel with pretty much the same character mix, but that would make very little sense within the over-all story arc of this film, leading me to think "sloppy editing" more than "clever set-up"! Several bits likewise seemed to have been edited down to their bare minimums, giving the impression that there was a 2+ hour film at one point that was cut down to an hour and a half at the expense of situation and character development.
Anyway, this wasn't a horrible film, but certainly wasn't one for me. Daughter #1 rather likes the Nancy Drew books, so this maybe worked better for her.