[mkeating]

I'm planning on buying my girlfriend a nice pair of headphones for the holiday. I'm looking for great clarity that will really shine with choral music especially. Also, she listens to classical, opera, and some rock. So I believe that I am looking for headphones with great midrange response. I'd also love to get her something comfortable and nice looking. I know a little bit about headphones but there are a lot of options. So, I'd appreciate some help here. Thanks.

 

[zazex]

Of course there are many, many options in that price range.  But many if not most of them are tailored for rock, hip hop, dubstep...
the popular music of the day.
 
For the uses you've mentioned, I'd suggest:
 
AKG K240 II - though the aesthetic is an acquired taste,
Audio Technica ATH-AD700
Grado SR 80i or SR 225i
Sennheiser 239, 518, or 558
 
These are all "open back" headphones which in my view suit classical music better
than do "closed back" headphones.  And they do well with rock & other genres too.
 
For closed back headphones in the price range, one I like a lot is the KRK KNS 8400.