Question speaks for itself...

Not sure what you mean by music box: do you mean that little box that plays music when opened? Or something more particular?

What do you mean buy a music box?? A radio yes!

If the lady in question likes trinkets, antiques, and music, then I would say yes.

It all depends on the lady!

She loves dancing (ballet, tap, jazz etc.) and I got this little ballerina music box and when you open it, it plays a sweet melody. Would that be a good gift for christmas or something? I would also give other things too of course!

Once again, it depends on her tastes. Does she like music boxes?

Even if it doesn't fit with what she currently 'likes', it could be nostalgic for her.

It sounds like a nice gift and like you are putting some thought into it which is a greater gift than the material part to some females.

Give from your heart and she should love it.