Diff'rent Strokes
No surprise here. Who doesn't like this theme song. I remember thinking the line 'they got nothing but their jeans" was just sad. Like why point out just how poor they were? I also didn't get why there were different versions but I preferred the one where they ended it by singing.
Mmmmmm.

The Jeffersons
This is my favorite song to sing when I'm moving up in the world and it doesn't matter where cause I'll still sing "to the eastside...in the deluxe apartment in the skyy-yy-yy. But who does not get some spirit and clap along to this:

Fish don’t fry in the kitchen;
Beans don’t burn on the grill.
Took a
whole lotta tryin’ just to get up that hill.
Now we’re up in the big
leagues.
Gettin’ our turn at bat.
As long as we live, it’s you and me
baby
There ain’t nothin wrong with that.

Family Ties
I remember watching this show and thinking all white families, all over the US were like the Keatons; upper middle class, two-parented households, happy, balanced, well cared for. What else did I have to go by? I barely knew real white kids growing up and the ones I did seemed to be just like them. It was just sweet, loving kind of song. Sha la la la.

Taxi
I reluctantly watched this show when I was little ('twas a bit too grown up for me) but I did like the jazzy, smooth theme song. It's no wonder some hip hop or R&B producer hasn't yet caught on and remixed this in a current song.

The Wonder Years
Ahhhh. One of the best. When this came on, I stopped what I was doing to stare at the screen and sing along. I actually have this on my iTunes and the full-length version is even better. Good soulful stuff!

The Greatest American Hero

Look at what's happened to me, I can't believe it myself. Suddenly I'm up on top of the world,

It should've been somebody else.

When I saw Fahrenheit 9/11 some years back, they played this song over a montage of our dear President Bush and I totally forgot I even knew the song and sang along to every word. Me and other people in the theater. I barely even remember the show, just this theme.

Welcome Back Kotter
Another on on my iTunes, I just think this is a great tune.

Golden Girls
I almost forgot about this one. Cause how and their momma ('cept mine) didn't like this song. I still know all the words and will put my own R&B flow to it.

Three's Company
(sorry, couldn't find the link)
Best known for its '70's 'wah wah' guitar intro, you just can't sing this theme song without smiling. And thinking of Jack Tripper. Oh how I loved this show.

Cheers
Classic! And probably my favorite. This was one of my favorite TV shows from the 80's and there as just a familiar, comfortable feeling when this show was on, like I was among friends (damn, that sounded corny, huh?)Nevertheless, I always hoped to have my own neighborhood bar to go to just like Cheers, wherever everybody knew my name.

Honorable Mention:
All in the Family -just classic
Sandford & Son -makes me think of junkyards and garbage, very '70s
Different World - always sang along
Hawaii Five-O - never watched a single episode but loved to dance to it, then cut it off.