I liked Orson Bean's Bilbo :) The voices in that cartoon were generally some pretty big stars--I liked the voices for Gandalf, Thorin, Gollum, and Smaug. "The Greatest Adventure" did have some wisdom in the lyrics; Glenn Yarborough got a little too much vibrato in the vocals though :) The songs I did really like were "Down to Goblintown" and "Fifteen Birds in Five Fir Trees".
Especially when he sang "Frodo of the Nine Fingers, and the Ring of DooooOOOOOOOOMMMM!"