Befriend, I am traveling at the moment and can't spend too much time wrting, but can say that in general tigers will not be an issue at all, nor will disease or kidnappings, but the mosquitos can be a bother, but not much more than that. So long as you act reasonably, you won't encounter difficulties. Thailand is wonderful.
One suggestion that I can make is to the effect that if you are looking to be in the northern part of THailand, and looking for a farang friendly Temple, Wat Sri Boen Ruang (Fang, Chiang Mai region) would be a consideration for you. Phra Greg and Phra Fred are two Western Bhikkhus there full time. Phra Fred teaches Dhamma, and Phra Greg teaches Vipassana. The Abbot, Dr. Apisit, is a young English speaking Thai monk; he is wel educated and supports the training of westerners at his Temple. There is a website at www.monkordination.com
that can provide more information.