Good idea, and good choice. Might I suggest a different background track for each page of the site?
I agree that classical, or, say, Death Metal is more appropriate than Olivia's own favorite music, since you want non-pop stuff that doesn't distract from reading the Gospels.
I suggest Faure's "In Paradisium"
http://www.youtube.com/watch?v=VUfi0ts_D-0