My advice for such a short trip is don't WASTE your time trekking out to Jersey Gardens (a kip IMO) or Woodbury (better but too far to be a good use of time) when you can get such great value in Manhattan.
For starters, with the weak dollar, even full price items are great value. Every store has sales on or discounted rails. Macy*s and Bloomingdales give 11% discount to visitors on production of your passport at the information centre. Add in DSW, Filenes etc and there are plenty of shops you can visit as you sightsee instead of wasting a full day shopping. I like Lexington Ave and the area around Union Square for shopping. Personally I think Macy*s is too big and prefer Bloomingdales.
For sights etc, I prefer Top of the Rock to the Empire State Building. Much more civilised queues (usually none at all), friendly staff and importantly, an amazing view of the Empire State Building.
One of my favourite ways to spend a day is subway to Ground Zero area, visit the site and St Pauls chapel nearby. Stroll down to Battery Park via the Famine memorial. Free roundtrip on Staten Island Ferry (don't get off on SI) to get a great view of the Statue of Liberty (sit on the right of the ferry). Subway to Brooklyn, Pizza in Grimaldis, stroll back to Manhattan across the Brooklyn bridge. Shopping at Union Square, back to the hotel, then out for a show followed by dinner.
I echo a previous poster in saying that a visit to the SOL and Ellis Island really is a full day trip and not really advisable for such a short trip. The view of the statue from the Staten Island ferry should give you good pics.
Personally I don't do the whole Canal Street thing. Counterfeit is not a good idea and customs and police are really cracking down, rightfully so. Do you really want to follow a stranger down a back alley in search of a knock off bag? That's Canal St these days. Gone are the visible stalls etc since the crackdown.