CM is a great place to start. I know it's not one of the places you listed, but we like staying here http://m.siripanna.com/default-en.html

When we go to Bangkok always spend a few days with our guide friend Tong. Www.tourwithtong.com it might be nice for your wife to have someone like tong with a nice car and driver take you to do some of the more adventurous things. We really like going to Kanchanaburi (sp). The elephant camp we went to there was well run. Another positive of having a local with you is that they can run interference for you so the hawkers don't bother your wife as much. Compared to many other places we have been, Thais are not too bad at this.

It's always a controversial thing, but you go to tiger temple or tiger kingdom.

You are sure to use the squatty potties wile you are there. Have your wife bring a small pack of wet wipes