Bob Rivers "The Chimney Song"
(If you haven't heard it, it's sung by a girl about 7 years old or so.)
There's something stuck up in the chimney
And I don't know what it is,
But it's been there all night long.
Well, I waited up for Santa all Christmas night
But he never came and it don't seem right.
And there's something in the chimney
And it doesn't make a sound,
But I wish you Merry Christmas.
There's something stuck up in the chimney
And I don't know what it is,
But it's been there all week long.
Well, the dog keeps barking up the chimney flue
And we don't know what we're going to do.
Cause there's something in the chimney
And it doesn't move around,
And it's been a week since Christmas.
There's something stuck up in the chimney
And I don't know what it is,
But it's been there all month long.
Well, it's jammed up tight above the fireplace
Now the house smells funny, such a big disgrace.
That there's something in the chimney
And it doesn't talk at all,
And it's been there since last Christmas.
There's something stuck up in the chimney
And I don't know what it is,
But it's been there all year long.
I'll been waiting up for Santa like I did last year
But my brother says, "He's already here."
And he's stuck up in the chimney
And he doesn't say a word
And he'll be there every Christmas.
And we'll have him every Christmas. 
You can hear it here, although it's been slightly sped up. 
http://www.superlaugh.com/cmas/chimney.htm
--ALSO--
"Zat You, Santa Claus?" the Buster Poindexter version. Louis Armstrong does the definitive version though I do prefer the harder to find Buster Poindexter. Garth Brooks should be shot for what he did to this song.
'Zat you, Santa Claus? 
Gifts I'm preparin' 
For some Christmas sharin' 
But I pause because 
Hangin' my stockin' 
I can hear a knockin' 
'Zat you, Santa Claus 
Sure is dark out 
Not the slighest spark out 
Pardon my clackin' jaws 
Uh, who there 
Who is it 
Uh, stoppin' for a visit 
'Zat you, Santa Claus 
Are you bringin' a present for me 
Something pleasantly pleasant for me 
That's what I've been waitin' for 
Would you mind slippin' it under the door 
Four winds are howlin' 
Or maybe that be growlin' 
My legs feel like straws 
Oh my, my, me, my 
Kindly would you reply 
'Zat you, Santa Claus 
Yeah 
Oh hangin' my stockin' 
I can hear a knockin' 
'Zat you, Santa Claus 
Yeah, say now 
Hey there, who is it 
Stoppin' for a visit 
'Zat you, Santa Claus 
Whoa there Santa you gave me a scare 
Now stop your teasin' 'cause I know you're there 
We don't believe in no goblins these days
But I can't explain why I'm shakin' this way 
Well I see old Santa in the keyhole 
I'll get to the cause 
One peek and I'll try there 
Uh-oh there's an eye there 
'Zat you, Santa Claus 
Please, please 
I'm bendin' my knees 
Is that you, Santa Claus 
That's him alright 
-Mikey