Hi,
I went to Thailand last Sept 07, had a great time and was a great experience.
The group of people were excellent we all mixed well together and the tour rep and tour guide were both excellent people as well. Was well looked after and the whole trip was well organised.
Hotels and food was very nice and the trips were great as well, you should do all the trips as they are all worth doing, some of the trips you have to pay extra for very cheap but worth doing.
You will have a great time and a great experience.