Bleach is superb. Disregarding the not-so-good Bount filler arc (which still manages to have some excellent fight sequences and music), everything just feel "real" and makes a lot of sense.
I don't follow Naruto but from what little I've seen it does seem rather "kiddy". Not something I would pick up at the moment.
Did not enjoy Blood+ much. The premise was good but the characterization was a great turnoff. Most of the major characters behaved much too stupidly, especially Saya. I did like the first and third opening theme a lot though. I continued watching the series hoping it would get better but it never did for me.