I agree with the recommendations of Thai egg roll and Pud Thai (sometimes you will see a version with tofu also) and coconut chicken soup. There is generally a shrimp version of the same soup. In Atlanta, at least one place serves a dish of salmon in panang curry. Strictly speaking I guess this is Thai style and not Thai, but it is very good. I say Thai style because I don't believe there is a salmon run in Siam.
A slightly more adventuresome item would be the Thai style hot and sour soups.
I suggest you stick to the mild and your husband to no more than the medium until you establish your tolerance for peppers. Some places offer mild, medium, hot, and "Thai" as their seasoning choices and the top one can be fierce. Ask for chili sauce and sliced peppers if you want to add heat. On request most Thai places will bring a rack with two kinds of chili sauce or red pepper and sliced jalapenos or similar in a sauce. Your husband will be able to season any dish to his taste. and I like fish cakes, but it can be a highly seasoned item here, and I've never been asked how I wanted it seasoned.
Fried catfish in a spicy stew is a more adventuresome item. I like it a lot. Also, you will often see lamb dishes. Some Thai people are Muslim.
Lemonade and salted lemonade, of offered, are good drinks. Lemonade made from salted lemons is a more substantial drink than plain lemonade - same as adding salt to a cooked dish enhances the flavor. Also, Thai ice tea or Thai ice coffee isa treat - sweetened condensed miklk is added to tea or coffee and it is like drinking candy. If you order a curry dish, I'd recommend plain rice and not fried rice. That way you can taste the curry without something else getting in the way.
The fisrt dessert to try is cocnut icecream. You are likely to see various other oriental flavors of icecream. One local place serves an excellent coconut cake.
Hope you enjoy and hope you will post a report.