Just replay it, you retard.
How can you know whether a game is good or not if you don't remind yourself why you liked it in the first place?
On, topic, the only games I'd have nostalgia for would be Neverwinter Nights 2, KOTOR 2 and Warcraft 3.
NWN 2 I replayed 2 years ago and it still held up nicely across all chapters. The first expansion is even better.
It's incredible how ugly the game looks today, and trying to make a good-looking female character without face mods will make you want to pour bleach over your eyes.
KOTOR 2 I finished again around the same time and while the game is good (gameplay being much better than in 1), it has some serious pacing issues at times, especially at the Telos station. People usually bitch about Peragus, but that part isn't as nearly as awful or boring as Telos is.
Other parts, like the choices you are presented with at Onderon, didn't sit well with me at all. Finally, the shitty lightning which makes everything look washed out is something I can't forgive. The game is on the same engine as the original, how could they fuck something so simple up?
Warcraft 3 I pretty much replay every year or so, just because it's so enjoyable.
Every time I play the campaign I am reminded how rewarding the cutscenes feel and how unintrusive and to the point they are.
The writing ranges from good, to cheesy to plain bland and uninspired like the majority of the Orc campaign, minus the missions with Grom.