In the normal daily riding the only thing that really matters is application. What kind of riding are you going to do? If you have good roads,700cc wheels with thin tires will make the ride easier. If you ride on trails and/or in snow,26" wheels with wide tires will be safer.

For me,I like the 26" wheels on my Safari. I can run skinny,high psi slicks in the Spring/Summer,and fat treaded/knobby/studded tires in the Fall/Winter. And I have many choices for both skinny and wide tires that are readily available at local shops. If I were running 700's,skinny slicks would be easy to find,but I'd have to search the web for tires much over 35mm.