The Diablo II video game soundtrack, by Matt Uelman is pretty much a staple at my gaming table. Why? Because, unlike most movie soundtracks, you can play this music in the background without a problem. Most movie soundtracks are cued for dramatic purposes, but this soundtrack meant for easy listening while playing a video game. There's few ups and down, sudden bursts of music, or anything like that. Which is perfect to play at the gaming table for your dungeon or horror-themed RPG.
Just listen to it.
The only downside is that the physical copy of this soundtrack can be hard to find now, given its popularity. You can find it on iTunes. And there's a 15 year anniversary version available that contains must from the original Diablo video game.
Oddly enough, the Diablo 3 soundtrack isn't as good. I'm not sure why. Maybe they were trying too hard to surpass the second game. It just doesn't have the same appeal.
Anyway, here's a few selections from Diablo 2.