Deleting accounts in vBulletin makes a very nasty mess of the database. You can probably have your account locked, if you wish.

But the simplest method is simply to stop coming here. You can delete the site from your bookmarks relatively easily, then change your password to something unmemorable and delete your cookies.

Of course, that won't stop you coming back for a fix if you really want one.

Most forum communities look unfavourably on 'goodbye threads' as they tend to be full of grandstanding by people who never actually do you the courtesy of leaving. Hence people are a little twitchy of the topic.