Originally Posted by
frankgg
Hmmm... We did the Erie Canal ride with 28's and it was fine, is the C&O path that much worse?
You can take a look at Bike Washington's C&O Canal Bicycling Guide and judge for yourself:
http://bikewashington.org/canal/plan-tires.php
Speaking personally, I would take a bike other than a skinny-tire bike if I could.
The components on the Orion bike look pretty bog standard modern, so I don't see why you couldn't move them over to the Nashbar touring frame if you wanted to. If you want to use bigger tire than 700x28, though, I'd consider getting a new set of wheels with wider rims.