I'm from the area and can confirm that the Hilton in Burnaby (Metrotown) is very close to a number of amenities. First off, it's about 2 blocks from the main sky train line, which can take you to downtown Vancouver. Second, it's next to Metrotown Centre, the largest shopping mall in all of BC. Lastly, there are large number of affordable restaurants along Kingsway for your guests. Most hotels can offer a group discount and guests can just call in, give a group code, and receive the group rate, but please confirm with them. Hope that helps.
The Hilton sounds like a good one, and another option might be the Grand Villa Casino Hotel & Conference Centre which is close to Highway 1 near the Willingdon exit. It's got really nice amenities and dining options and is rather fancy and quite new, however I guess it's not as convenient as the Hilton and entertainment is largely related to gaming....
Good luck with your planning!
Click on each tool to see a sample.