For classical music I've found it easier to just go with the flow (path of least resistance) and add the composer as the artist. Yeah, the composer isn't the artist. But software like MC and other media players and all of the various portable players expect that there be an artist and expect to sort by artist. So I fill in the artist field with the composer to keep them happy.
In general I try to follow the
Classical Style Guide from MuiscBrainz for what fields to fill in, how to do album titles, how to do track titles, and other style issues for classical music. Their style guide works well and works well with MC, other players and portables (like my iPod). I don't follow the style guide exactly. I deviate as it suits me. I use the MusicBrainz style guide as a general guide.
For the album title I give the album a sensible name and add the primary performer/conductor in parenthesis at the end
So, as an example
Album: Bach Concertos (Hilary Hahn)
Artist: Bach
Composer: Bach, Johann Sebastian (1685 - 1750)
Conductor: Hilary Hahn - violin / Jeffrey Kahane - Los Angeles Chamber Orchestra
Publisher: Deutsche Grammophon / 474 199-2 / 2003
I do need to go through at clean up my conductor and performer tags for all my classical albums. Right now I lump a lot in the conductor field (it's easily searchable, so it's not a big deal). I should separate that out one of these days.