What is the best way to get from the airport to old town?
We used a shuttle bus. It was a little slow with a couple of stops but got us there. Don't know about best.
Cheap and quick. Bus from Airport to Metro, metro to old town.
"Best" depends on your priorities.
We took a taxi. It wasn't terribly expensive. It was quick, easy, it took us straight to our hotel, and dropped us at the door. That was best for us. What's "best" might be different for you.
If you have Rick's Prague book, he outlines all the options, from cheap to expensive.
If you want more details, you'll have to provide us with what you mean by "best" (cheapest? fastest? least amount of walking?) and exact location of your accommodation (some of the inexpensive methods go near a part of the old town but are not close to other parts).
We arranged a taxi through praguetransport.com for our first visit to Prague. The British driver pointed out landmarks along the way and shared suggestions for local dining options. Very pleasant to work wth and reasonably priced. We love using public transit, but enjoyed having a little guidance in a city that was new to us.
There are various "book in advance" options where you can pay when you get here. If you take a taxi from the airport then you usually speak to the dispatcher first and tell him/her where you want to go. He/she then tells the driver and you'll get an accurate price quote. Personally I always give the driver the address printed on a piece of paper so no problems with "wrong address". Expect to pay @CZK600 to the Old Town. It's a balance of time vs price. You can find cheaper but when you get a shuttlebus it will usually take longer.