Thanks, everyone, for all the information! There's a lot I didn't know. My personal preference would be to stay off oxygen for as long as possible, but at this point I'm just not sure which would benefit me more. It sounds like everyone has had a different experience...
As far as the moaning in my sleep, my mother's told me I've always done that. I never thought there was actually a reason behind it, though. Being tight in the lungs would make sense.
I will be sure to talk to my doc about it the next time I see him, just to be on the safe side and get his take on it. Thanks again for all the help!