>First, any suggestions on hotels/locations I should stay for one night in Vancouver pre-cruise? Do I stick w/ downtown?

Definitely stick with downtown. Your cruise will either depart from Canada Place (right in downtown) or Ballantyne Pier (on the edge of downtown).

The hotels that are right at Canada Place are very nice:

Pan Pacific Vancouver:
http://vancouver.panpacific.com

Fairmont Waterfront Vancouver:
http://www.fairmont.com/waterfront/

....however they are pile-driving as part of the convention centre construction, so I'm not sure if that's noisy in those hotels at night. Probably not, but I'd ask.

>I think the Four Seasons is a pretty decent option at that price, but I'll let someone here confirm that suspicion.

Yes, of the ones on your list it's also the closest to the Canada Place Cruise ship terminal.

>Second... what should we do? We arrive at 10 am on a Friday and have about 24 hours to do whatever.

You won't be able to fit all of these in in 24 hours, but here are some suggestions from which you can pick-and-choose:

Stanley Park: North America's third largest urban park, which juts into the harbour on a peninsula (http://www.city.vancouver.bc.ca/parks/parks/stanley/). The six-mile seawall around the park provides excellent views of the city, harbour and north-shore mountains. You can walk some or all of the seawall. Bikes are also available for rental near the entrance to the park. The world-renowned Vancouver Aquarium is also in the park (http://www.vanaqua.org).

Granville Island: This former industrial site has been transformed into an artsy neighborhood with quaint shops, cafes, bookstores, pubs, theatres, restaurants and a large public market (http://www.seegranvilleisland.com/). A fun way to get to Granville Island is via The Granville Island Ferries or the Aquabus (http://www.granvilleislandferries.bc.ca/map.html). You can pick up a ferry at the southern foot of Burrard or Hornby streets.

Canada Place: If your ship departs from Ballantyne you should definitely visit Canada Place, at the northern foot of Burrard Street. (http://www.canadaplace.ca/cpc/Tourist_Information/). The perimeter walk provides great views of the harbour, city and mountains. Vancouver's IMAX theatre is also at Canada Place (http://www.imax.com/vancouver/).

The SeaBus: This passenger catamaran provides a fifteen minute crossing of the harbour for under $3 CAD (http://en.wikipedia.org/wiki/SeaBus), delivering visitors to Lonsdale Quay, where you can watch tugboats heading out to service Vancouver's busy working harbour (http://www.lonsdalequay.com/).

Grouse Mountain: Located in the North Shore Mountains, Grouse features a 100-passenger gondola ride up the mountain, providing spectacular views of Vancouver and the surrounding mountains. You can also rent skis or snowshoes.
(http://www.grousemountain.com/). Sunny days only!

University of British Columbia Museum of Anthropology: Learn about the indigenous cultures of Canada at this museum (http://www.moa.ubc.ca/), then explore the campus of one of Canada's largest universities (http://www.attractions.ubc.ca/).

Gastown: The oldest commercial district in Vancouver, best known for its Victorian-style architecture (http://www.gastown.org/). Home to Storyeum, an interactive museum about the history of West Coast Canada (http://tinyurl.com/dfh3n).

Vancouver Art Gallery: Formerly the courthouse, this neoclassical building houses over 177 of Canadian artist Emily Carr's paintings (http://www.vanartgallery.bc.ca/about_gallery.cfm)

Robson Street: Vancouver's premier shopping boulevard is lined with restaurants serving food from all over the world (http://www.robsonstreet.ca/)

Have a good trip!

Cheers,
Geoff Glave
Vancouver, Canada