Pallys with awesome skills have taccs in their bloodstreams so no they dont need too if your a pally and not as awesome as joe then its a good idea to check it out
The 4 first bosse is optional in what order to them. We did shannox first last night, so read up on all 4 first bosses to begin with
I played Classic until I was nearly level 60. It needs The Burning Crusade really for me though. I am lurking around Daggerspine again for a while, trying to get used to the changes lol