Ok.. not sure where to start, so I'm just going to order the games by the platforms I played them on and from least to most known. Also note that there will be a whole spectrum of songs, so If you don't like one, you might as well love the next one. Ok so lets start.
N64
Top Gear Rally I hope you have surround sound headphones, or speakers. If not, you will only hear main song in your right ear and the backing stuff in your left.... sorry..
Diddy Kong Racing Its a kids game with fast, tense mostly happy upbeat music. I really like all of them and you can listen to the whole soundtrack here
...Time stamps to different songs in the description, but...
PC
Gothic 3 Has a lot of nice tunes, but just a few quick examples
Cabal online This was a MMORPG game, that I think no longer exists. One of my favorite soundtracks. Some examples:
Quick mentions that you probably know already:
