Posters don't have the ability to delete threads. The one you made hasn't had any responses in over five months - why not just let it die a natural death?
You could file a request with the Admins (T'Bonz or AntonyF) but as Misfit Toy stated, it's easier to just let it die. If you hadn't mentioned it, nobody would even have noticed its existence. Just start a couple of new threads or resurrect old ones and spam your thread gradually down the list to the very bottom. Btw such technical and administrational questions are best asked at QSF instead of here.
Threads don't get deleted, just closed. Which is excellent IMHO. Places that delete threads don't get my patronage.
Most threads don't even get closed, they are just left to die a natural death. I've always thought requests to delete old threads were a bit silly/odd, though. If no one's posting in it, and it's old, who cares? It's not hurting anyone.
Amen. It is possible for myself or one of the other MISC mods to delete a thread in this forum, but it's generally something that we only do as a last resort (like a pornography thread for example). My understanding is that deleting threads is not easy for the server to do.