I love Bach
I have not yet found anything of his that I haven't liked. First time I heard one of the Cello suites I thought wtf, but after getting used to the cello I think they're marvellous.
Chopin has been a favourite lately. (Hey, if "The Pianist" wasn't good for anything else I'd watch it for the music
)
Grieg's "Morning" and especially the first part of "Solveig's Song"
Also (I don't think he's been previously mentioned here) Sibelius.