Skyrim holds the top spot, for obvious reasons. 

2nd: Dark Souls. I may have barely noticed the music in the boss fights while I [i]cursed, panicked, wept, begged for my life, and begged for my souls,[/i] whenever I lost, and howled my triumph to the skies when I won, but the music made it all the better. 

3rd: Demons souls, for above reasons.