Japan veteran here. I would say itinerary 1 rather than 2 - Osaka doesn't have that much that Tokyo doesn't - I'm sure any Kansai-dwellers will shout me down, but if you've only got a week, I wouldn't do the two biggest modern cities, and if you're going to do one, it's got to be Tokyo.
Is there any reason you're not considering Kyoto, also on the shinkansen, slightly closer than Osaka - it's much more of a contrast to Tokyo and is the centre of most Japanese traditional culture, has all the famous zen gardens etc?
Hakone is good for views of Mount Fuji, the lake etc, and it's nice to stay in a ryokan and try soaking in one of the hot springs. You can also go to Hakone on the shinkansen, but it's a very short trip, not on the fastest kind, and you have to change trains to get to the resort. There are also some interesting museums, sculpture gardens etc there.
If you're not going to do Kyoto, it might be worth considering a day trip to Kamakura from Tokyo to see some of the temples, big buddha etc.
Akihabara is a definite must-do - if your DH is a geekish type I would recommend he does lots of online research in advance about which shops he wants to go to as it's huge and confusing.
The other must-do I'd say is to spend a couple of hours in a branch of Tokyu Hands (I think the Shinjuku one attached to Takashimaya Times Square is best). This is what hardware/stationery/department stores should be like....
I wouldn't bother with DisneySea without children unless you are real Disney fans - yes, it has different attractions and rides from DisneyLand next door, but it seems a bit odd to go all the way to Japan for a week and spend one day in a little slice of America...
If you do plan to go to Kyoto or Osaka, it might be worth getting a Japan rail pass for a week, which gives you unlimited use of JR trains (includes some overground lines in Tokyo, but not subway) - it usually costs slightly less than the price of return shinkansen tickets to Kyoto. You can only buy them outside Japan.
Yes to letting your bank/credit card company know you are going - my credit card got blocked last time I was there. You can use overseas debit/credit cards to withdraw cash in atms inside 7-Eleven convenience stores and at Citibank atms, but other bank atms often won't take foreign cards. Post office ones used to, but I had trouble with them this year.
If you haven't found it already, I'd recommend the japan-guide website for lots of useful trip planning stuff, and a good forum for asking lots of questions.