Festival of the Lion King!!!!!!
We saw both, and while Tarzan was 'OK' the FOTLK was just wonderful. The music, the singers, the costumes, everything. I think it is one of those 'intangibles' that you cannot really put into words. (until you see it that is).
So....Lion King gets my vote! (we saw it 3x as a family in January, and I saw it once again on a solo trip in April)