Thank you all for the wonderful advice.

Just got back from Tokyo and wanted to share, despite the warnings re. the platform transfers within the various stations - we found them to be very manageable, and well signposted. Nothing too dissimilar from getting off the Airport Express in HK Station and making your way to the Island Line.

- We took the Skyliner from NRT to Ueno, then to Hatchobori and finally changed to Maihama. Thought this would be a major hassle at 8pm but we were safely at our hotel by 9:40pm.
- Managed to ride the Asama and the Max Toki trains in Green Class - short but nice rides anyway for my son.
- Took the NEX back to the airport from Tokyo Station which was an easy connect from Maihama.
- Did a loop on the Tokyo Disney Monorail as well, and managed to buy him the Plarail version of the Monorail from the Disney Store.

All in all, a much easier trip than i anticipated.

Next he wants to sit in the front seat of the Romance Car to Hakone (he saw a picture of it in a Japanese Train Book i bought him!).

There are many interesting pieces of rolling stock on the non-JR railways throughout Japan. For your next trip, maybe check out the Fujikyu Railway which has some interesting trains:

http://e.fujikyu-railway.jp/train/

Thanks for the trip report. It really brought a smile to my face.

Cool report! Shhhh. Don't tell people it's easy on the trains. To many visitors already...:-)

hey, OP, did you make it to the train museum in Omiya?

Yes we did - took the asama train there and the max toki back.

The museum - and by now we are connoisseurs of train museums worldwide - was excellent! Hk, Delhi, several in California, Germany and in the U.K. - I would say that the Omiya museum was the best thus far.

Very cool stuff! Thanks for posting back how the trip went. I didn't post because I didn't have anything to add that hadn't already been said, but I've been watching this thread with interest. Very glad you were able to give your son a great introduction to Tokyo's trains.

"The seats on the Fuji Tozan Densha are reserved seats. In adition to the train ticket, thereis an additional 200 yen fee for riding this train. In the event the train is full, you will not be able to ride the train. We ask for your understanding in this matter. Each seat is not reserved, so once you have boarded the train please sit wherever you like. " - talk about confusing the gai-jin :D

Make sure to reserve seats for this in advance. Check the schedules too--specific types of rolling stock are in service for different times. I recommend looking for the VSE train. You can also buy a cute romancecar VSE-shaped bento on board there.

I didn't go to the Saitama train museum, but the Kyoto one is probably the best train museum I've been to. Granted, I don't have your extensive experience.