At their peak Zeppelin were a fine, fine band, but for sheer length of career, versatility (from R&B band through witty pop singles, rock operas, intelligent lyrics and a powerhouse live act) it has to be the 'Oo.
Instrument for instrument it's a close call:
Moon v. Bonham. Probably a draw. The two greatest rock drummers of their era, with different styles, but both astonishing.
Entwistle v. Jones. Entwistle win, easy.
Daltrey v. Plant. Plant at his peak wins easily, but you have to say that RD made the most of what he had, and has kept in better shape for longer. Draw.
Townshend v. Page (as musicians). Looks like an easy win for Page, but I dunno. PT is not just a powerhouse rhythm player, he has real skill, and always harnessed it to the needs of the song. Multi-instrumentalist, too. Draw.
Townshend v. Page (as songwriters). Townshend by a street. Probably the most intelligent and thoughtful rock musician of his g-g-g-generation.
Love 'em both, though, and glad to have been around when they were both at their peak in the early 70s.