I am not astonished that I picked the film with the most votes - An American Werewolf in London is just spectacular, the chage scene is still one of the best and when it comes to scares, I can only point out the double (make that tripple) dream scene -
Fantastic film!
I also thought the Wolf-Man remake was good and bad in places, it is ok to own, I think.
I recall having liked Wolfen, but it is way too long ago since I last saw it...
The first Ginger Snaps was really good too, the sequels never did much for me, as far as I remember...
I cannot think of the worst film with werewolves, but there was one we watched at a friend's place, I can only recall that there was a lot of Spanish in it, because we were chatting so much, the only one liking it a bit understands Spanish and turned uoff the sub-titles...
On a side note: I really love the TV Series Being Human and it fits here as they have werewolves in it - although the wolves looks rather funny, but it is just a great show - the UK original more so than the US Remake...