OMG is this still going.
TINAS: Are you female?
Tandem Jeremey idea of a Transalp is sensible idea, as is say an Africa Twin. TJ is hitting the nail on the head.
If you want a single, then go XT600 for a good old round compromise (main prob would be motorway stuff: transalp, africa twin etc better at this). If you want smaller more offraodable get a DR350, if you can find one in rght cond for money.
I'd be dubious of a single any bigger than a 660cc. DR600's were ok, but you'd get a much newer XT (in whatever guise)for the money. Dan Walsh from bike rode XT round the world. I know of a group who took DR350's round the world.