So, no one really watches a Christmas themed movie hoping for intense, long-term, life altering plots (do they?). If that is what you are seeking just watch 'It's a Wonderful Life' and skip all other Christmas movies.
Anyway, I enjoyed this movie, and love that it is super family friendly without being child-like. The characters have nice chemistry and the scenery and costumes are stunning. If you like Hallmark Christmas movies and their ilk, you'll really enjoy this movie.
If you don't like those type of movies, don't click the play button, and perhaps go for a more cynical Christmas movie such as Scrooged .
(Also, I never watched High School musical, so I have no background on how that plays into this movie).