Are the Beatles the Greatest rock band in history?

Yes. What followed them would not have been except for them. They opened the world of popular music to change (for the better) than any group before or since.

Well that's a matter of opinion, but in terms of innovation, record sales, critical regard and fan base, I would say yes.

I could go on all day talking about their unique sound and masses of talent too, but then that would be presenting my opinion as fact, and I did state to myself that I would try to refrain from doing so

Led Zeppelin

That's a matter of taste.

Some people thought (or think) they are amazing, others - like me - did not ever particularly rate them.

I thought the Stones were far better, at the time.

Yes

to me, yes… followed by The Beach Boys, Chicago, Eagles, and Journey

I don't know if "most celebrated" amounts to "the greatest".

i don't know if "most celebrated" amounts to "the awesomeest"...

If you think so.