I was there a couple of weeks ago for a conference, which didn't give me a lot of time to explore the city, but - it is now on my future list for a vacation base. It is a lovely city. I thought it was architecturally very interesting - a little like Chicago. The Canada Place area is where the big cruise ships come in (again worth seeing). Shopping - good but no bargain city!
Things to do:
Walk around the 7km of Stanley Park
Take a seaplane tour of the city
Have dinner in the Blue Water Cafe (if you like seafood). £££ but fantastic - plan for £80-100 per person with a decent wine and a cocktail.
http://www.bluewatercafe.net/I didn't have a bad meal whilst there.
Safety. I chose a little boutique hotel (converted motel) about 1.5km from the Canada Place area, and walked back and forth up and down Burrard St, sometimes twice day. Never had any sense of threat. There are no-go areas (E Hasting St) but there is no real reason for you to venture there. There are a fair number of beggars, but they were courteous and not threatening. One held the door to the 7-11 where I got my fruit/yoghurt for breakfast, and gave me a cheery good morning - needless to say he got most of my loose change!
I envy you going there. We have 2 weeks in SoCal this year but Vancouver might be on the list soon.