I highly recommend the Performace Bike Forte Metro K tire @700x35. I've run this tire for years in both its 26"x1.25 and 700cx35 version on both our tandem and triplet, including loaded touring on gravel and some bad rail trail surfaces that I'd just as soon forget. Best of all, they are crazy-cheap. Currently on sale for $11.99 each. At that price you can get them and keep them just for special occasions like this and not feel guilty.
http://www.performancebike.com/bikes...1511000_400237