We have been to Paris many times and have stayed in the 8th, 4th, 6th and 7th. Each has its advantages. Since you probably will be roaming around a bit, don't worry so much what is right outside your door, but how you can wander around, take the metro or bus and see the things you want. We probably prefer the 6th and 7th because of the neighborhoods, restaurants and markets, but it takes more than one trip to Paris to really decide what you like best. Relax, and have fun.

Thank you for all the helpful responses! I love to hear all your different reasons! It has for sure made my decision easy! I'm also glad to know that you pretty much can't go wrong. I mean it's Paris!

Thanks again! We're super excited!