Doesn't matter where you got married as long as you have a certified translation of your marriage certificate notarised by the Thai Ministry of Foreign Affairs. Yes, you need to be working in Thailand but since 2008 don't need PR first, if you have a Thai wife.

For further information, please see this thread http://www.thaivisa.com/forum/topic/121353-story-of-my-thai-citizenship-application/

What's the point? If you have a kid just put all your property, company and land in the kid's name. Your kids are going to get it anyway. Thai Passport is useless for travelling outside Asia.