What with me considering remakes and remasters to be very different things, and what with my penchant for talking too much, I'll give you two answers.
Remaster - Spyro Reignited Trilogy
I've loved the original Spyro games since I was a child and replay them every single year. The desktop background on every laptop and PC I've had for about ten years has been a slideshow of Spyro levels. I just love them. They're simple, satisfying, beautiful games that have so much whimsy and childish fantasy about them that they charmed me as a kid and are one of the few things that still bring me a pure kind of joy.
I was glad to hear they were remastering them, but I was also worried in case they drained from the games the things I loved, which are kind of intangible and thus easy to mess up. But much to my delight the remaster took nothing from them. Gameplay is unchanged from the originals, meaning it feels identical to play. I can choose the original soundtrack (a masterwork by Stewart Copeland) over the new one. And it looks simply gorgeous. It's one of the most artistically beautiful games I have ever seen in my life. I just want to grab everything and take a big bite out of it, like a delicious cake.
The only changes of note are the dragon designs in the first game and some of the voices. The new dragon designs aren't bad, but they lack the regional consistency of the original, which I always liked from a world building perspective. As for voices, it's a rare issue, but some lines that have been branded in my mind for decades are delivered without much energy or character this time around, but this only affects some lines and I still hear them as they were in my head anyway.
The Spyro remaster is pretty much a straight upgrade of the original. The same game except it looks twelve thousand times better. Or is it fourteen thousand?
Remake - Resident Evil 2 (2019)
I recently did a whole blog about how much I love this game. It takes the core of the original — its premise, its basic narrative elements, and its design goals — and uses them to construct something that is familiar but entirely new at the same time. REmake2 captures the essence of the original but presents it in a way that is far more modern, not just in terms of gameplay but in terms of presentation, too. It successfully bridges the gap between late-90s survival horror titles and contemporary games by getting rid of clunky gameplay mechanics like tank controls and even loading screens and replacing them with direct action and the illusion of a persistent world.
This is one of the best horror games out there and you do yourself a disservice by not playing it.
Honourable Mentions
Crash Bandicoot N. Sane Trilogy
Resident Evil (2002)
Hitman Contracts
Super Mario All-Stars
Ocarina of Time 3D
Majora's Mask 3D
The Wind Waker HD