I've seen it several times over my life....I've always enjoyed it. I'm sure at some point it will get the live action treatment like every other Disney movie. I imagine the scene with the dogs going at it over a plate of spaghetti and meatballs will garner this one a PG-13 rating at least.
I saw it about a thousand years ago. I thought it lacked the Disney touch. The quality of Disney movies went steadily down as Walt did less and less direct supervision. What the company does now is not even in the same league.
I have the sad duty of admitting that throughout my entire childhood, I never saw even one Disney animated movie, and even later in life, I can only name fewer than five of the old classic ones that I've finally seen. "Lady and the Tramp" is not among the ones I have seen.