I agree, smurf everyone.
Anyway, best album? If forced to choose at gunpoint I'd probably have to go with The White Album just because of the variety. Also, many of their best songs are on it - "Blackbird", "While My Guitar Gently Weeps", "Julia", "Happiness Is a Warm Gun", etc. Abbey Road and Revolver are also strong contenders.
There are a large number of candidates for best Beatles song ever. "A Day in the Life" is certainly one of them. Apart from the White Album songs I mentioned, I'd throw on "Strawberry Fields Forever", "I Am the Walrus", the whole suite on Abbey Road starting with "You Never Give Me Your Money", and probably a number of selections from Revolver. From the early period I really like "No Reply" and "I'll Be Back", but let's be honest, there was a period there where they started outdoing themselves with virtually every album (with the arguable exception of Beatles for Sale). Some of the early stuff is great, but it really doesn't hold a candle to their later psychedelic weirdness. The Beatles are a great exhibit for the "Drugs have done good things for us" school of argument.
Of course we all know how popular they were, but tons of artists have been popular and not had lasting value. The Beatles have. The number of bands who would not exist, or would sound radically different without, the Beatles is so massive that I don't really even know where to begin. There are only a handful of artists from the same era who can make a legitimate claim to having influenced as many musicians - Bob Dylan, the Velvet Underground, Neil Young, and maybe Miles Davis. A few other contenders would come around later - possibly '70s-era Pink Floyd. (Yes, Floyd's early stuff with Barrett, which started around '66, is great, but it's not Beatles-level influential).
Anyway, great band. I could write a lot more about them but it's been awhile since I returned to their music. Might go back to it this weekend.