These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
YMMV: Grandma Got Run Over By A Reindeer
Adaptation Displacement: There's quite a lot of people unaware all the songs in the special are a huge chunk of the other Dr. Elmo Christmas songs.
Big Lipped Alligator Moment: Every musical sequence, although one has the excuse of Grandpa being a Cloud Cuckoo Lander. The only song that truly has much connection to the story and is actually referred to is the title song.
The ET reference that lasts for all of ten seconds when Jake meets the elf in his room.
Dude, Not Funny!: At one point during Jake's search for Grandma, Daphne actually tells Jake to give up looking for her in probably the coldest tone ever. It's pretty jarring in an otherwise family friendly movie.
Moral Event Horizon: The fact that Cousin Mel was perfectly willing to poison innocent strangers just to get Grandma to sell the store put her over the line.
So Bad, It's Good: The voice acting sounds, at times, incredibly stilted and several characters were given actors that aren't well-suited for the part; the jokes and puns are almost always groan-inducing; and the animation isn't anywhere near as fluid as it could have been. Even so, it's really hard to dislike this special, Adored by the Network notwithstanding, mostly because of issues with the production.
It doesn't hurt that Cousin Mel is incredibly hot.
What an Idiot: After spending so much time with an Amoral Attorney, you'd think Cousin Mel would know better than to just suddenly confess literally EVERYTHING.
Possibly justified, as Cousin Mel is pretty much It's All About Me personified. Naturally the moment things were turning against her, she'd confess to try and get a lighter sentence.
Not to mention all the evidence against her.
She was pretty much boxed into a corner at that moment, so what else could she have done?