I have just started watching some of the earlier episodes I've been able to get copies of, and my kids watch them also, and love them! I will say, though, that seeing Big Bird the way he was in episode 1 (compared to the way he looks today), was a little confusing for my 3 yr old. When she asked me "Mommy, what happened to his head?" I really had to think fast! The explination I decided to stick with was this: I explained to her that "these were some of the first Sesame Street programs ever filmed and, back then, big bird was just a baby! And since many baby birds, like robins and such,are born without feathers, back then Big Bird still had some major feather growing to do!" She seemed to accept this with no problem, but now, when she wants to see early SS she still says "Mom, can we watch the SS where Big Bird has no head?" LOL!
Also, as an afterthought, I think I know why I never remember Oscar being orange even though I watched SS from day one; and thats because, back then, most T.V.'s owned by middle class familys were black and white, like ours was. So when Oscars color changed, people like me probably didn't even notice it!