Itinerary Advice - Tokyo in December

i will be visiting in tokyo from 12/23 to 12/30 as a family with 3 teenagers. could anyone advise with regards to this basic itinerary? we are willing to go anywhere as far as nikko. thanks in advance!

day 1 (12/23/07 - sun)
afternoon: arrival at narita at 4:55pm
[question] would it be better to take a limousine bus from NRT to century southern tower hotel? or to take the narita express?
evening: stay around shinjuku

(since 12/23 is the emperor's birthday -- and thus, national holiday, are there any things to watch out for?)

day 2 (12/24/07 - mon)
morning: shinjuku
afternoon: harajuku/omotesando/meiji shrine (oriental bazaar)
evening: shibuya

(since the previous day was a national holiday, but a weekend also, are there any things to watch out for on the following day?)

day 3 (12/25/07 - tues)
morning: kichijoji
[question] i'm interested in having lunch at satou steakhousee in kichijoj. does anyone have suggestions on reserving or anything?

i also need activities to do in kichijoji or that would not be terribly far from kichijoji in the afternoon and/or evening.

day 4 (12/26/07 - wed)
morning: tsukiji market
afternoon: daikanyama

[question] what is near daikanyama? are the ebisu gardens worth wisiting?

day 5 (12/27/07 - thurs)
morning: ?? i need suggestions.
afternoon: roppongi
evening: odaiba
[question] i'd like to visit the technology/science museum in odaiba during this trip, but i understand that it is closed sometime in late december. when is a good time to visit instead?

day 6 (12/28/07 - fri)
suggestions?

day 7 (12/29/07 - sat)
morning: kappabashi shopping street, kaminarimon, sensoji temple, nakamise/shinnakamise/asakusa
afternoon: akihabara
evening: ginza

day 8 (12/30/07 - sun)
departure

At 16.55 h arrival it is difficult to catch the 17.30 h Limousine bus to Century Southern Hotel, the next bus is 19.00 h. There is a direct Narita Express to Shinjuku at 18.13 h.
On a national holiday ( and when Sunday the national holiday, then Monday ) offices, banks are closed, shops are open. Expect the Museum of Maritime Science and the Museum Science and Innovation, both in Odaiba, to be closed from Dec 28th till New Year. On that Friday you can make a one day trip to Nikko, or maybe of more interest for the teenagers to Hakone area. ( Because of boiling earth, ropeway, pirate ship, checkpoint aso ).

Thank you for your response! We've already visited Hakone on our last trip... so we're more inclined towards Nikko. However, we're afraid that Nikko would be too cold in late December.

However, regarding Nikko, which plan would be better for visiting Nikko? The JR free pass? or Tobu free pass? Why is there such a large price gap? The two trains take the same amount of time if I'm not mistaken.

Take a day trip to Hakone. Buy a day pass to use the train, bus, boat, cable car, tram and train back to Tokyo. It's an outdoor excursion and you can see Mt. Fuji at a distance on a clear day. If you're lucky you can catch the newer bullet train (Romance Car) to Hakone.

HIGHLY RECOMMEND!

We took the Romance Car (Odakyu) to Hakone last time, went to eat the black eggs from the hot springs, rode the cable car, took the boat tour around Lake Ashi, and spent a night at Washintei Hougetsu Ryokan. If we do visit Hakone, is there anything else worth visiting?

In my opinion Tobu Passes give better value for money than JR Nikko Pass. If you do shrine only without lake you can visit Edo Mura with the teenagers. Too Cold? Difficult to reply. I had the impression it is "warmer" than a December day in Northern Europe.

Are there any other areas in Tokyo worth visiting?