The Gold Standard:
"Potter's House of Horrors"
http://pottershouseofhorrors.com/
This thing is incredible and takes you a good 20 minutes to walk through, and it's very scary -- not the type of place where you want to linger, when you have an axe murderer following you. It's a plant nursery in the summer time and they convert it into a huge mother, scary scary haunted house. They also have creepy actors with professional level scary makeup who just sidle up to you in the lineup and stare at you while you are waiting your turn to go in. SO CREEPY!
Honorable Mention:
"Dunbar Haunted House"
http://www.dunbarhauntedhouse.com
This one looks pretty good, but I only learned about it today. You can see some video of patrons inside under 'screams'.
"Haunted Forest Scream Train"
http://bctrains.com/Spooky-Details.htm
This one is great, complete with a "Chainsaw Charlie" wearing a Michael Myers / Jason type of mask.
"PNE Fright Nights"
http://www.pne.ca/fright-nights
This is in the local amusement park -- it's pretty good, but I probably wouldn't do a repeat visit.
"Stanley Park Ghost Train"
http://vancouver.ca/parks/events/ghosttrain/index.htm
This one is pretty tame and definitely for kids. I would probably say that it's for the age 6-8 set. Just the situation of being on a train moving at a snail's place in a dark forest is probably scary enough for some little kids. It's more 'theatrical' and interpretive than scary, I would say.
Anyone else?