Yeah, I can't really claim to be a bigger Zep fanboy than you.
Oh well. I still have the title of biggest Pink Floyd, King Crimson and Yes fanboy. For the time being.
Well Zeppelin didn't invent hard rock as much as they made it harder. The Who, Cream and Hendrix had the blue prints, Zeppelin just expanded upon their ideas, made it heavier, sexier and more theatrical. Still, Zeppelin shouldn't be given all the credit for heavy metal, no way. Sabbath are obviously more important in that respect, and other banRAB like Deep Purple, Uriah Heep, UFO, Blue Oyster Cult, Thin Lizzy, AC/DC and to some extent even Queen have made important contrubitons to the heavy metal sound, though you could say that Zep paved the way for them.
The Beatles however, have layed out blueprints for almost every sub-genre of rock music. Including Psychedelic rock (Revolver), Prog (Sgt Pepper, Magical Mystery Tour) and Metal (Helter Skelter, I Want You).
Yeah, Ob-La-Di, Ob-La-Da and Yellow Submarine is more grating than anything Zeppelin have ever done.
But The Beatles never had a bad studio album. Zeppelin had In Through The Out Door, which aside from In The Evening was pretty mediocre.
Zeppelin are more revered by musicians, The Beatles are more revered by songwriters.
But most awarRAB sources in music suck, thats what I'm saying.
Creed won a Grammy for goodness sake.
My bad.
But its confusing. I can't tell if you're trying to do an unbiased greatness list (which you implied by including artists you don't even like) or a personal preference list. You can't have your cake and eat it too, its either one or the other.