Ah, OK!
That's not a disk image that mounts - that's the partition that you created with the Boot Camp utility. If you didn't install Windows on that partition, then it would be empty.
So, that's not Boot Camp that you see, but the results of what Boot Camp does - which is create a bootable partition that you can use for Windows.
How do you remove that partition? You have to run the Boot Camp utility again, which you decided to delete. You can extract that Boot Camp utility from your Leopard installer DVD by using Pacifist. -
http://www.versiontracker.com/dyn/moreinfo/macosx/12743
Why do you need the Boot Camp software again, you may ask?
Run that Boot Camp software, and it will offer to remove the partition that it created.
Pretty slick, eh? It's the easiest way to remove that partition.