Well first I saw Wrong Turn on HBO and it was one of the WORST MOVIES EVER MADE. So if House of Wax is crap (haven't seen it, and hopefully never will) so what, it isn't like Eliza has not been in a bad horror movie either. And her part in True Lies was very limited (hence why I wouldn't bring up 24 for Cuthbert, both great pieces of film/television however both starring in minor roles that were obviously the least important to the writers and therefore most annoying to the audience, albeit Kim Bauer for all her nusances has had a bit more to do) and I never held Buffy in high regard. Haven't seen Soul Survivors (nor heard of it) and while Jay and Silent Bob Strike Back was a deent flick (not Kevin Smith's best) again her role was so limited it didn't matter as her partners were played by extremely bad actresses like Ali Larter and the infamous Shannon Elizabeth.
For the record Cuthbert has been in some dogs (I have not seen House of Wax but will take your word for it that that was a crap movie), but The Girl Next Door while forgettable and a bit of a knock-off of Risky Business was a highly entertaining teen flick and one of the better ones of the last decade (not saying much as it was only decent) and The Quiet seems to be a pretty good thriller if a bit morbid and disturbing in which she is suppoesed to be pretty good.
I would hardly call either a great actress by any mean and likely neither would be considered for Black Cat if she ever makes it to film, but I think Cuthbert looks more the part and more importantly has demonstrated herself to be a more capable actress.
Now what about Kraven though?