Mostly orchestral but generally any OST you thought was great. Videogames, films or otherwise.
Speaking of which there are two videogames I played recently with some of the finest orchestral pieces I ever heard these are -
First and foreMOST - Journey - incredible game and in terms of OST you would be challenged to find better once you play through and realise how perfectly it fits, I mean the comments alone on the video I will share speak of people literally buying a PS3 and the game JUST from hearing the music...
The other is of course, Shadow of the Colossus. For similar reasons (not quite up to par with Journey, but its still a class A effort)