As far as I know, they don't curl hair - they just do one of the three styles. My DD7 got the Disney Diva, which involved putting her own hair in a ponytail (it is shoulder-length), then putting same-colored hair extensions in that were curly and matched her hair color. (Don't have her picture posted - DH is funny that way.) That is probably the closest style to the Belle look. You can see that style in posts 12, 14 and 16 in the link (and probably other posts too, but I stopped looking). If your DD has brown hair already, it would be a pretty close look to Belle when she is dressed up. You could add the headband yourself, or your Fairy Godmother might be willing if you ask when you get there.
Both my girls loved it, although DD4 did not want the makeup done. DD7 was all over the makeup!
Hope this helps!