magix, no prob, if u need any help let me know. let me noe where u going for ur last 2 days, then i can give u suggestions..
zhu zhu, dun worry, in fact, JR pass allows u to take their bullet train.. it's pretty complex, hope i can clear up some of the doubts.
In japan, there are many railway/mrt companies (owned by private unlike singapore). JR is one of the companies which own major railways lines in Japan. It connects many parts of japan. in this JR railway, it includes buses, railway trains(which stops at every stations) and also include the bullet train as well! There are few types of bullet trains in japan(forgot the name of the trains). For this JR pass, we can take all bullet trains owned by JR except for the fastest bullet train. however, trust me, their 2nd fastest train is fast too.. travelling from narita airport to kyoto takes about 3-4 hours of journey only!
If u wan to visit osaka, my suggestion to u is tt u still stay in kyoto.. travelling from kyoto to osaka is only abt 40 mins and accomodation in kyoto is cheaper than osaka. In fact osaka is jus another tokyo. If stay in osaka n tokyo only, i think it will be too bored. mainly shopping and pple everywhere. Kyoto is the most reccommended place for tourist where u can find beautiful shrines and temples. Nice sceneries too... also, travelling between osaka, kyoto and nara are only within an hour journey. Nara is famous for it's deer park where the deers roam freely.. very fun.. also the popluar "dong da men" is located there as well.
My advice is travel light. For me when i went with my FH, we only carry 2 big bag packs (with trolley attached). the train is big enough to accomodate ur big luggages, however, it might b difficult to carry up n down staircases.
Hope the above explaination does not confuses all of u. If there are more questions, i will try to ans if i know..hope i m not too long winded meanwhile enjoy your prep for ur trip..
last thing, esp if u r going f n e, rem to buy a guide book. buy the one from lonely planet. very useful with maps and suggested itinery. u wun regret buying it. if u wan to see my photos, do leave ur email down n i will send invite to u.