I can’t say I’m a Bangkok expert, as I haven’t spend here that much time. That said, I have some recommendations for you:
Bike tour with Co van Kessel
Founded by Dutchy and Bangkok local Co van Kessel, this company offers very nice and fun bike tours. With some lovely guides, you can experience parts of the city that you otherwise wouldn’t have seen. Safe with your feed from the dirty ground, you will drive through markets, backyards and on some platforms above the water or even rice fields! Maybe not really a budget thing (1000B pp/3hrs), but it’s worth it. more info
A surprisingly nice museum. Descriptions in my guidebook didn’t sound attempting, but with some time to kill, we decided to take a tuktuk and see the place for ourself. It’s a little oasis midst dirty and crowded Bangkok. With some very cute (free) guides and lots of history and art, the house of the former silk-guru is more interesting to visit than I expected. Also, you only pay 100B to get in 🙂 1 Wang Mai, Pathum Wan, Bangkok 10330
Fun and convenient travel through Bangkok by very cheap ferry’s with an orange flag (15B/ride). Enjoy the breeze, views and local experience. There are about 15 stops along the river, marked with numbers. Getting of at N13 will bring you to Khao San Road and N3 is next to the River City where Co van Kessel bike tours are situated. Find more info about interesting stops on the orange ferry here
Although very very cliché and nothing cultural about it, you can simply not visit Bangkok without taking a look at the Khao San Road. It’s a statement for the rest of your trip through party Thailand. Here, you will find all souvenirs and touristcrap you will see in any other tourist place in the country times 100. Get your (fake) Lonely Planet, North Face backpack, Havianas and not so fake tattoo or piercing for the rest of your tour. There are also some nice 2nd hand bookshops on the western part of neighbour Ram Butri street.
We were staying at The Chilli Hotel, close to China town and the River City mall with access to the Orange flag ferry. It’s not the most fancy room, but staff is very friendly and prices are reasonable. If you look for a place to stay around the airport, I can recommend to choose a hotel close to the Paseo Mall. I think it’s the only area where you find something else to do than just being locked up in your hotel room. With lot’s of restaurants, shops and a market, you can easily entertain yourself for a couple of hours.