Given that you have to travel long distances to go to church, I suggest you read a couple of books before you go.
This first book, The Orthodox Church, by Bishop Kallistos (Timothy Ware), a convert like many of us, covers some basic things. However, later editions, such as the ones you will most likely find available, do have some revisionist material. If possible, get an earlier version of the book.
http://www.amazon.com/exec/obidos/tg/detail/-/0140146563/qid=1062679977/sr=1-1/ref=sr_1_1/102-4476042-6607321?v=glance&s=books The next book is the Law of God by (Archpriest) Seraphim Slobodskoy. I couldn't find it on amazon.com, or ebay. But i did find it on half.com by ebay at
http://half.ebay.com/cat/buy/prod.cgi?cpid=1416166&meta_id=1 you might have to sign in. If so, the link above might not work. This beautiful book goes into great detail about the faith and practice of the church.
It seems your fiance does not like change; that is good of course, because we have not changed our services much since the founding of the church by the apostles. The Divine Liturgy which is celebrated in Orthodox churches everywhere throughout the world on Sundays (and other feastdays) was written by St. John Chrysostom in the 4th century. However, it seems to me that your fiance will have to open his mind to the fact that Orthodox practice is not like a latin mass. Yes, he will hear the creed and the Lord's Prayer, but the service is different; it hasn't changed like RC mass.
Finally, I suggest you call in advance before going to the Orthodox church. Tell the priest your circumstances so he can be more prepared.
May the Lord direct your steps,
In Christ,
Reader John
We have The Law of God, and it is a lovely book. I don't read it often enough.