Whilst it is a stereotypical Christmas film it is an archetypal example of what a Christmas film should be. Anyone sitting down with their notepads out analyzing a film like this is just a Scrooge. It doesn't need to be over-thought, it is a Hallmark production which follows a strict guideline as to what a feel-good Hallmark production has to be (family).
To criticize Danica McKellar in the lead-role seems an odd thing to do. You know what to expect from a family film. Any other actor would have had to act the part in exactly the same way. There isn't room in the role or in the movie as a whole to be experimenting with method-acting or "what's my motivation?" and getting deep and dark with the character - again - it's a Hallmark film.
As well as an actor, Danica is a mathematician (or the other-way- around?) and would suggest her accepting this role was purely for fun and to have Christmas months in advance! She chooses roles that won't clash with her scholastic career too adversely and must balance these two very different careers.
The interaction between herself and the young lead comes from a genuine place. Being so bound to a past role when a child is the bane of all actors - the character she is eternally manacled to is an anagram of "epic inner woo". Danica is epic as an example of how to avoid finding too much of your inner woo and going of the rails when vulnerable and young. She survived early-fame, looks even more attractive now and can wryly smile to herself that she has the credentials to play a part like this without any fear of any dented Porsches coming back to haunt her. For this reason alone, the film is just that much more charming and is what gives it the propulsion it would have lacked had just about anyone else played her part.
It has a start, a middle and a fairytale ending...but we already knew that!