Engine overheating and No heat inside the car?

I drive a '00 Jetta.
On my drive home from work one cold February night, I looked at the
dash to learn the coolant was overheating. Many people would think the
temperature gauge translates to the engine overheating, but that's not
neccessarily the case. I cranked the heat inside the car to hopefully
remedy the situation, only to find cold air coming from the vents.
Now I'm no mechanic, but I know how to handle a wrench, and hoping it
was the cheapest (and easiest) thing that could possibly be causing the
problem....thermostat. Took out the thermostat out of the car and
submerged it in a pot of hot water..this works just fine (water boils
212 F). My thermostat is supposed to open in the neighborhood of 180
(it'll say right on it) and it was fully open before the water was to a
boil, so I was confident that wasn't the problem. My wallet began to
whimper.
I can't drive my kid around in the cold, so I'm forced to immediately
take it to a shop.
Told them my story...they vacuumed out the entire cooling system and
filled it to the brim so there were to air pockets. They drove it for
about 10 minutes...had heat in the car for about 5. Same symptoms came
back. Let it cool back at the shop...discover air pockets have formed
and the only explanation is that combustion gas (when and where the
gasoline is actually ignited and the explosions occur) which,
infortunately means the head gasket has failed (or blown, as it's
known). <--hey that rhymes!!
In replacing that, I had the water pump replaced as well. My car's got
98,000 miles, so it's probably a good idea to do it now.
Timing belt was also stretched out pretty good, so they replaced that
as well.
TOTAL BILL : little over a grand
I'm not complaining - this car has ran great the entire time I've had
it and these repairs had to be expected once you're knocking on 100K
miles.
Car idles and drives even smoother now, don't have the breathing noise
that it had before the repairs.