I would suggest a Continental Ultra Gatorskin in the 700x25 size. It's not a touring-specific tire, but touring-specific tires generally don't come in such narrow widths. If you want a touring-specific tire, there are many, many, many available, but you'll generally have to go somewhat wider.
Low rolling resistance and flat protection are somewhat opposing forces, so you normally compromise on a tire that is adequate at both.
Could you clarify what you mean when you say 100 pounds? What does that include? You? your bike? your total load? your load on one wheel?
I'll note that many posters here aren't going to like the constraints you put on your question, and will probably be trying to talk you into wider tires. I'm not sure you you decided on such narrow tires, but you should probably consider relaxing this constraint.
Last edited by John Nelson; 10-26-09 at 08:24 AM.