Hi!
I woke up today in the mood of the season... IT'S CHRISTMAS!!! :)
So I decided to share my (basic) knowledge on the Holy Night (or Silent Night, as you wish) Chords.
It's very simple, and it is suposed to be played slow, 'cause it's a calm and beautiful song that everyone is familiar with.
This is my first attempt to put Chords or Tabs here, so, be easy on me! :)
Now, on to the music:

These are the chords you have to know to play this song:

    G   D   C   Em7  D7                                E A D G B e
e[---3---2---0----0---2---]
B[---3---3---1----3---1---]                       {G} [3 2 0 0 3 3]
G[---0---2---0----0---2---]                       {D} [x x 0 2 3 2]
D[---0---0---2----2---0---]          or...        {C} [0 3 2 0 1 0]
A[---2-------3----2---0---]                      {Em7}[0 2 2 0 3 0]
E[---3-------0----0-------]                      {D7} [x 0 0 2 1 2]


And now you play like that:

**********************************
 G
Silent Night Holy Night
 D          G
All is calm all is bright
 C            G
Round yon Virgin Mother and Child
 D            G      Em7
Sleep in heavenly peace
 G      D7        G
Sleep in heavenly peace

**********************************

It's it, more or less... At least, it's how I play it and i think it sounds pretty good.
Thanks to my friend who teached me it! :)
Now go under the Christmas Tree and start rocking your family's reunion with this song! :)
Hope you enjoy it!
See you,
Your friend,
Rui Silva from Portugal