For reasons of privacy I either need this account to be completely deleted or the nickname changed, to assure that it can't be "tracked back" to my actual identity. If other people don't care about their privacy, that's none of my concern, but I do, and that's why I asked if it's possible.
If you used a username that can be used to "track you down" (as you put it) then I suggest you be more careful next time on any other site. Also, your e-mail and ip adresses (which are the most dangerous data in terms of privacy) are something that the staff doesn't publicize. They are private and never was such data given to anyone other than the staff.
But like everyone else said, if your account is to be deleted, it has do be done by one of the admins, namely Zise, though it has been required many times before and never done so I wouldn't get my hopes up. Anyway, send him a PM.
PS- I know of no forum where you can delete your account like that yourself btw.