Ok, this is mostly a question on selling pets but not in a normal way.

I play on another site where players take unwanted pets and set up a topic that is a 'Pick a Door' (or some form of variation) and have other players pick a random door (or what ever the 'pick a--' is labeled) and get a random pet for cheap/free

for example (though I don't think I need to give one as I'm sure other players are familiar with Pick a Door), say I have 5 doors all set to 50g and one player picks and pays for door 3 and gets whatever pet is behind that door. Another player picks/pays for door 2 and gets the pet behind that door.. It goes on till all doors are picked.

I don't see an actual 'Give Away' Forum, so would this be best suited for Games and Contests even if it's a kind of pay to play sort of thing? I really don't want to release them because a lot of these pets are decent in some form or manner xD

Yes, that would be something that belongs in the games and contests forum. :) I've seen many games of pick a door being played there. ^^ And it's fine that it's pay to play. Just make sure that you clearly state that it is before the game starts.

Oh good :) I haven't really explored all the forums beyond the first page so I didn't know that Pick a Door was done here too XD