This is how I like to play this song.

Chords:
G   320003
C   x30210
D7  xx0212
C/B x22010
Am7 x02010
Sometimes I find myself playing Am instead of Am7 and it still sounds good so if 
it is easier for you go for it
Am  x02210

Strum Pattern:
DDUUD
From "My grandpa" to "sing some too" I strum once per chord.
On the split measures I just do DD for each chord. The split measures are G D7 on 
the last line of the verses and C C/B in the chorus.

Verse 1:
G                     C
My grandpa he's ninty-five
G                              D7
he keeps on dancing he's still alive
G                     C
My grandma she's ninty-two
G                                D7
she loves to dance and sing some too
G                          C
I don't know but I've been told
G                                        D7
if you keep on dancing you'll never grow old
G                       C              G          D7        G
Come on darlin' put a pretty dress on we're gonna go out tonight

Chorus:
C     C/B    Am7                 G
Dance Dance Dance x3 (All night long)

Verse 2:
G                      C
I'm a hard workin man I'm a sun of a gun
G                              D7
I been workin all week in the noonday sun
G                          C
the wood's in the kitchen the cow's in the barn
G                          D7
I'm all cleaned up and my chores are all done
G             C          G                D7
Take my hand come along let's go out and have some fun
G                       C              G          D7        G
Come on darlin' put a pretty dress on we're gonna go out tonight

Chorus

Verse 3:
G                      C
Well come on darlin' don't you look that way
G                      D7
don't know when you smile I've got to say
G                              C
You're my honey-pumpkin-lover you're my heart's delight
G                    D7
don't you want to go out tonight
G                           C
You're such a pretty lady you're such a sweet girl
G                           D7
when you dance it brightens up my world
G                       C              G          D7        G
Come on darlin' put a pretty dress on we're gonna go out tonight

Chorus