Well, now, this is a tricky one, because I really don't tend to like the kinds of inspirational songs people expect to be played at funeral. I either like super sad songs which are just horrible to play in that kind of situation, or super silly songs that don't fit at all. So I think I'm going to go with Chris Rice's rendition of "O Freedom," which musically fits the mood I'd want and lyrically fits my view on death.
I had SO MUCH TROUBLE FINDING THIS. There are absolutely zero workable videos on YouTube. So I'm using the MySpace music player. I haven't tried embedding this before - hopefully there will be no problems with it.