I too highly recommend 400ASA as a good all-round film speed.
I'm not too sure if these days you need to worry about the x-ray machines at the airport affecting your film, someone else here may know for sure.
A flash unit (as already mentioned) may be handy at some point.
I'll go out on a limb here and suggest an alternative to a small tripod.
I know how quickly it becomes bothersome to lug around all the acquired gear especially in a foreign country and the less gear you are seen carrying, the better.
In terms of ultra portability and considering you'll be using say a 28mm and a 50mm lens, why not try making yourself one of these.
http://www.metacafe.com/watch/104194...se_the_tripod/
Worth considering in any case.