1) The Windsor Tourist is a decent bike but the wheels might be a little weak. If you go that route, you might want to run the wheels by a wheel-builder for re-tensioning.
2) If you don't have a bike (and are riding it), sooner is better (and ride it). Keep in mind that you'll do the big trip after some experience. Most people start out carrying too much and carry less when they've been on a few trips.
3) Keep in mind that 29'er MTB wheels are 700c wheels. It might be easier to get tires and replacement wheels for 26 inch. You might want to carry a fold up tire, regardless.
4) Get a complete bike and swap things out that you find are problems. Building your own won't be cheaper and it really is a better idea for somebody who really knows what they want.
5) Panniers. Easier to fly with. (Trailers appear to work fine on the road.) A trailer might have the same problems that the 700c wheels do (hard to repair/deal-with in remote places. In the worst case, it would be cheaper to ship panniers or a rack than it would be to ship a trailer.
6) Do you wear a helmet normally? There was one study (in England) that suggested that drivers give non-helmeted riders more leeway. No one knows whether it's a universal phenomenon. Don't base helmet use on that one study.
7) Disk brakes have the same sorts of problems that 700c wheels have (hard to get parts and replace in remote places).
8) Don't worry too much but if it's easy to do, cover it (at least, cover your seat).
Last edited by njkayaker; 11-05-10 at 06:53 PM.