The hotel at the airport is the Novotel Suvarnabhumi. It's the nicest of the airport hotels and the closest as well as the most expensive. I've sometimes found great deals on www.agoda.com for it, but you have to prepay.

The Best western is fairly close, not as expensive, not quite as nice, but fine (according to a recent review by someone I know and trust).

You have lots of choice from BKK to HAN. Thai Air and Bangkok Air both fly this route. Air Asia, a budget carrier, flies this route if you don't mind the inconveniences of a budget carrier. Lots of big international airlines fly this route, but the risk is that the flight may get into Bangkok way late, impacting on your flight to Hanoi. Those international carriers often have great prices, though. Take a look on expedia, for instance, and you'll see Qatar come up as one option, Air France also flies this route on some days. But you'll have to check for your particular dates to see who makes the flight on your date.

try air asia or vietnam air to hanoi... we flew vn air last fall...

I also flew Vietnam Air--In fact, I was on the same flight as Rhkkmk (Bob). Flight was fine and on time each way.

My husband and I stayed at a place called The Residence Airport & Spa Hotel. It was cheap...around $40. The place was "ok"...not great, but ok for the price. The issue I had was that it was not close to the airport. I think it took about 20 minutes via taxi. Once there....NOTHING is close by. We took a taxi to a large mall and were pretty disappointed. Nothing there of interest. But-- if you just need a cheap place to crash and are not interested in anything but a clean bed and a marginal breakfast, than you might check this hotel out.

I paid $60 on agoda in January 2010 for the airport Novotel. It was super easy to get to (free shuttle to and fro) and super-luxurious for the $. Highly recommend.

user, that's the lowest price I've heard for the airport Novotel. You got a great deal!