They're awesome, but they're a little ways out of town.
Downtown Victoria is a pretty fun place to window shop. The Royal BC Museum is interesting. Craigdarroch Castle is pretty cool, my kids got a kick out of going to a "castle," even if it's really just a big,old house. I've only spent long weekends there, so I'm not sure what I'd do with a full week. We had some fun driving around neighborhoods, especially along the water.
If your kids like the Old Spaghetti Factory in the states, just know that it's quite different there. Have fun!